F-35 News
Moderadores: Glauber Prestes, Conselho de Moderação
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Re: F-35 News
E os da USAF fizeram uma estreia desastrosa no vietna, com a perda de 2 aparelhos nos primeiros 5 dias, salvo engano...
- Bourne
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Re: F-35 News
Acredito que seja em relação ao conceito dos projetos superestimarem as inovações e um novo tipo de guerra que nunca realmente ocorreu.
No caso do F4 se supunha que os combates aéreos entre caças tinham acabado e os canhões desnecessários. O resultado foi uma surra nas primeiras versões dos MiGs do Vietnã. Depois remendaram o projeto para contemplar essas necessidades. Não tinham tempo a perder. Era guerra fria. Se estavam sendo violentados pelos vietnamitas. A coisa seria terrível contra os soviéticos. Considerados no caso dos sucessores que vierem bem rápido para assumir a linha de frente com F15, F16, F14 e F18.
Para o F35 o problema seja investir excessivamente na furtividade e como uma aeronave multiuso demais. Vão continuar investindo nela, mas vai mudar muito. Ou os números serem reduzidos em favor de outra aeronave. Em parte ocorreu com o F22. Hoje se fala em um substituto com melhor capacidade e mais barato. A Boeing também não é boba e sonha com o substituto do Super Hornet para Marinha, talvez oferecendo a USAF.
No caso do F4 se supunha que os combates aéreos entre caças tinham acabado e os canhões desnecessários. O resultado foi uma surra nas primeiras versões dos MiGs do Vietnã. Depois remendaram o projeto para contemplar essas necessidades. Não tinham tempo a perder. Era guerra fria. Se estavam sendo violentados pelos vietnamitas. A coisa seria terrível contra os soviéticos. Considerados no caso dos sucessores que vierem bem rápido para assumir a linha de frente com F15, F16, F14 e F18.
Para o F35 o problema seja investir excessivamente na furtividade e como uma aeronave multiuso demais. Vão continuar investindo nela, mas vai mudar muito. Ou os números serem reduzidos em favor de outra aeronave. Em parte ocorreu com o F22. Hoje se fala em um substituto com melhor capacidade e mais barato. A Boeing também não é boba e sonha com o substituto do Super Hornet para Marinha, talvez oferecendo a USAF.
- LeandroGCard
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Re: F-35 News
É que ambos os projetos, assim como o F-35, visavam produzir poderosos caças de combate que incorporariam os conceitos mais avançados e o que havia de mais sofisticado na tecnologia americana, e deveriam dar aos EUA e a seus aliados a superioridade tecnológica na arena aérea pelas décadas seguintes.henriquejr escreveu:Leandro, fiquei curioso com essa comparação em relação ao F-4 e F-111. Seria por que eram considerados caças "pesadões" e com pouca agilidade??? Se puder explicar eu agradeço!
O F-4, uma iniciativa privada da MacDonnell Douglas, após alguns problemas iniciais em serviço acabou se mostrando de fato um excelente e versátil avião de combate. Foi o esteio da USAF e da USN durante a Gerra do Vietnã, ajudou a salvar Israel na Guerra do Yom Kippur e foi operado por diversas nações ao longo de décadas, chegando a um total de mais de 5 mil unidades produzidas. Nunca foi capaz de garantir por si mesmo a superioridade aérea para os EUA, mas foi sem dúvida um grande sucesso.
Já o F-111, uma iniciativa apoiada pelo próprio secretário de defesa e que contava com todo o apoio do governo americano, foi desenvolvido uma década depois, e em princípio pôde incorporar conceitos ainda mais modernos e mais avanços tecnológicos que o próprio F-4. O objetivo inicial era obter um super-caça, algo como um F-14 com capacidade também para ataque ao solo, e com desempenho excepcional em todas as altitudes contando para isso com os mais sofisticados recursos que os engenheiros americanos pudessem desenvolver. Mas o resultado foi uma aeronave com restrições de desempenho tamanhas que levaram ao abandono das missões de caça e ao seu uso somente em tarefas especializadas de penetração e ataque em baixa altitude ou reconhecimento. Apenas a USAF o adotou, e o fabricante ainda conseguiu empurrar algumas unidades para a Austrália. Nenhum outro país se interessou pelo avião e o número de unidades produzidas ficou em cerca de dez por cento do número de F-4's. Um indubitável fracasso, apesar das promessas e dos recursos empregados no programa.
O tempo dirá com qual destas histórias a do F-35 se parecerá mais.
Leandro G. Card
- kekosam
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Re: F-35 News
Só uma pergunta: A USAF ainda opera o EF-111 Raven? Ou está dependendo dos Prowler/Growler da USN?
Assinatura? Estou vendo com meu advogado...
- P44
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Re: F-35 News
F-35 Fighters to Cost $90m Each (edited excerpt)
(Source: The Australian; published February 28, 2013)
The Joint Strike Fighters to be bought for the RAAF will cost about $90 million each -- much more than the $67m claimed by its manufacturer, says the American general appointed by the Pentagon to straighten out the struggling program.
…/…
After briefing Australian defence officials on the JSF at the Avalon air show in Victoria, General Bogdan said some of the problems he encountered with the program were ugly. But he said an effective remedy had been to force the manufacturer, Lockheed Martin corporation, to share the cost of fixing faults and covering delays.
Once the company had "skin in the game", its performance improved significantly, General Bogdan said, and he was confident the program was getting better "not as fast as I want it to but it is getting better".
…/…
General Bogdan said his role was not to be a cheerleader for the JSF and he certainly did not sound like one as he delivered his warts and all update. In a very frank briefing, he said the aircraft would probably cost Australia $90m to $92m each.
"You hear Lockheed Martin keep talking about $65m, $67m. Well, guess what. That's the cost back in 2004 or 2003.
“Who cares about that? I want to know what it costs the day I buy it," he said. (end of excerpt)
Click here for the full story, on The Australian website. http://www.theaustralian.com.au/nationa ... 6587211618
-ends-
(Source: The Australian; published February 28, 2013)
The Joint Strike Fighters to be bought for the RAAF will cost about $90 million each -- much more than the $67m claimed by its manufacturer, says the American general appointed by the Pentagon to straighten out the struggling program.
…/…
After briefing Australian defence officials on the JSF at the Avalon air show in Victoria, General Bogdan said some of the problems he encountered with the program were ugly. But he said an effective remedy had been to force the manufacturer, Lockheed Martin corporation, to share the cost of fixing faults and covering delays.
Once the company had "skin in the game", its performance improved significantly, General Bogdan said, and he was confident the program was getting better "not as fast as I want it to but it is getting better".
…/…
General Bogdan said his role was not to be a cheerleader for the JSF and he certainly did not sound like one as he delivered his warts and all update. In a very frank briefing, he said the aircraft would probably cost Australia $90m to $92m each.
"You hear Lockheed Martin keep talking about $65m, $67m. Well, guess what. That's the cost back in 2004 or 2003.
“Who cares about that? I want to know what it costs the day I buy it," he said. (end of excerpt)
Click here for the full story, on The Australian website. http://www.theaustralian.com.au/nationa ... 6587211618
-ends-
Triste sina ter nascido português
- Carlos Lima
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Re: F-35 News
Eles utilizam os Growler da USN.kekosam escreveu:Só uma pergunta: A USAF ainda opera o EF-111 Raven? Ou está dependendo dos Prowler/Growler da USN?
O EF-111 saiu de serviço a um tempão.
[]s
CB_Lima
CB_Lima = Carlos Lima
- P44
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Re: F-35 News
F-35 Grounded After New F-135 Engine Problems
(Source: JSFNieuws.nl; published February 22, 2013)
By Johan Boeder
There have been several instances of turbine blades breaking off on the Pratt & Whitney F135 engine. Shown here are several broken blades during the first known incident, on Aug. 30, 2007, which ultimately led to the engine’s re-design in 2008. (photo P&W)
KESTEREN, Netherlands --- On Thursday, February 21, 2013, the Pentagon Friday ordered the grounding for all F-35 aircraft, after a routine check at the Edwards Air Force Base revealed a crack in a low pressure turbine blade in the engine of an F-35A.
This is but the latest incident concerning the Pratt & Whitney F135 engine, as during 2007-2009 repeated problems with turbine blades led to significant delays in the test program and a partial redesign of certain parts of the engine.
On February 19, 2013 a routine inspection took place of a Pratt & Whitney F135 engine at Edwards AFB, USA. During the inspection using a borescope, there were indications that there was a crack in a LPT turbine blade. It was confirmed after further investigation. The turbine blade is sent to Pratt & Whitney in Middletown (CT), USA for further investigation.
Statements from JSF Program Office
The F-35 JSF Program Office said in a Feb. 22 statement to the press: “It is too early to know the fleet-wide impact of this finding, however as a precautionary measure, all F-35 flight operations have been suspended until the investigation is complete and the cause of the blade crack is fully understood. The F-35 Joint Program Office is working closely with Pratt & Whitney and Lockheed Martin at all F-35 locations to ensure the integrity of the engine, and to return the fleet safely to flight as soon as possible.”
Lt. Gen. Chris Bogdan, head of the JSF Program Office, suggested in a briefing in Australia that if the crack's cause was as straightforward as a foreign object striking the turbine, or a basic manufacturing defect, “I could foresee the airplane back in the air in the next week or two.”
Bogdan added that “If it's more than that, then we have to look at what the risk is to the fleet,” adding than a verdict on the cracking's cause was expected "by the end of this week", Reuters reported from Melbourne.
Some facts about what happened
It was a F-135 engine with 700 hours, of which 409 flight hours. The aircraft was the F-35A test aircraft AF-2. The half-inch wide crack was found in a turbine blade of the low pressure turbine section. This makes it unlikely that it is caused by so-called FOD (Foreign Object Damage), such as a bird strike, because such an object has to pass the Fan Section (3 stages) Compressor Section (6 stages), combustor and high pressure turbine section before reaching the low pressure turbine section.
Cracks in turbine blades in the low pressure turbine section usually are caused by high thermal or other stressing loads of the turbine blades. The forces in the 40.000 lb (about 29.000 hp) engine are enormous. A grounding after such a discovery usually takes relatively short (e.g. one week), normally a manufacturing error or some incident is the root cause.
Until then, for safety reasons a grounding may be the standard procedure. Reuters reported Feb 24 that “In fact, two jets were airborne at air bases in Maryland and Arizona and had to be recalled, said one of the sources.” At this moment, all 51 F-35s, of all versions, in use at several airfields to support the test and training program, are grounded.
Long history of engine problems since 2006
It cannot be excluded that the root cause of the current problem is more structural than a simple manufacturing error or an isolated incident. Since 2006 there had been a series of engine problems with the F-135 engine.
In May 2006, Aviation Week reporter David A. Fulghum wrote a detailed article “Joint Strike Fighter F135 Engine Burns Hotter Than Desired” and described the risk of a shorter engine life or engine damage caused by higher than expected temperatures on the F-135 engine.
In August 2007 and February 2008 there were serious problems. Turbine blades broke off suddenly by a form of metal fatigue. The cause was sought in a combination of factors.
On 30 August 2007 in test engine FX634, after 122 hours of testing, a turbine blade in the 3rd LPT stage broke off completely. On February 4, 2008 something similar happened to engine FTE06, also in the 3rd LPT stage, after 19 hours.
These problems with the engine contributed significantly to the delays in the JSF test program for the period 2007-2008.
Redesign of the engine in 2008
In early 2008, an engine, the FX640 ground test engine, was equipped with numerous sensors and instruments. On April 21, 2008 a test process was started to find the cause of the problem. Through a detailed test plan the forces and tensions that arise in the engine were mapped in different power ranges.
At that moment it seemed to be primarily an issue of the F-35B STOVL (vertical landing) version. The cracks in the turbine blades were created in exactly the same place, and seemed to occur when switching from forward to vertical drive. Later in 2008, the results became available. The blade cracks seemed to have been caused by certain vibrations that triggered a material failure.
This led to a redesign of a number of elements in the engine. One of the upgrades was a change of the distance between the turbine blades. After the redesign the engine was retested and recertified. At the end of 2008 Pratt & Whitney issued a press statement, saying that they were convinced that the problems were solved.
(UPDATE: A link to a July 22, 2008 briefing by Pratt & Whitney on F135 blade failures was removed on Feb. 28 at the request of the F-35 Joint Program Office. The "information in those slides has the potential to compromise the safety of our pilots," the request stated -- Editor.)
In 2009, problems with redesigned engine
In July 2009, the then head of the JSF Program Office, Marine Corps Maj. Gen. David R. Heinz, was still was not happy with the F-135 problems. He told the press: “The problems include too many individual blades that fail to meet specifications, as well as combined “stack-ups” of blades that fail early. I’m not satisfied with the rates that I’m getting.”
A few days later he was ordered by the Pentagon not to comment publicly on problems with the F-135 engine.
In September 2009, serious engine problems were again revealed during testing of the Pratt & Whitney F-135 engine. At a crucial moment in the debate in the U.S. Congress on the choice of two competing engine types (the Pentagon wanted to axe the alternate engine (the GE / Rolls Royce F-136), a Pratt & Whitney F-135 engine broke down. Again, the cause seemed to lie in broken turbine blades. However, this time the same problem occurred in the new, redesigned engine with redesigned turbine blades.
Engine problems continue until now
After the problems in 2009, officials no longer publicly commented about the engine problems. Also there were no indications that there actually were problems with the engine or that there were any reliability issues.
In April 2011, however, Admiral Venlet, the then Head of JSF Program Office, told reporters that some engine problems were impacting on the delivery schedule.
The grounding last week puts the engine back in the publicity spotlight. However, this time it is not the complex F-35B STOVL version, but the much simpler engine in the F-35A, the Air Force version, that failed, which has led some observers to speculate that the problem could be more deeply ingrained in the engine’s design.
History of previous F-35 groundings
May 2007: The first incident was recorded in May 2007, when the F-35A prototype AA-1 experienced an electrical short that disabled flight controls on the horizontal stabliser. A grounding was ordered and continued until December 2007, due to time needed to redesign several parts of the 270-volt electrical system and F-135 engine problems.
July 2008: On July 23, 2008, both flying F-35 prototypes were grounded after problems were detected with ground cooling fan electrical circuitry, DCMA reported on Aug 18, 2008 that tests were delayed as a result of testing anomalies on the 28 Volt and 270 Volt Battery Charger/Controller Unit, the Electrical Distribution Unit and the Power Distribution Unit. It was due to design problems. Flights were resumed first week of September-2008.
December 2008: On Dec 12, 2008 the F-35 was grounded again as a result of engine and ejection seat anomalies. Seat anomalies were observed in ejection seat sequence during an escape system test on Nov. 20, 2008. It took nearly 3 months to solve the problems and aircraft AA-1 did not return to the skies until Feb. 24, 2009.
May 2009: The F-35 fleet didn’t fly between May 7, 2009 (84th flight of prototype AA-1) and Jun 23, 2009. No comments were available from JPO or L-M.
October 2010: F-35 fleet grounded after the fuel pump shut down above 10,000ft (3,050m). The problem was caused by a software bug.
March 2011: The entire F-35 fleet was grounded some weeks after test aircraft AF-4 experienced a dual generator failure. After both generators shut down in flight, the IPP activated and allowed the F-35’s flight control system to continue functioning. The problem was traced to faulty maintenance handling.
June 2011: Carrier-based F-35C suspended from flying after engineers at NAS Patuxent River discovered a software problem that could have affected the flight control surfaces. Grounding was from 17 June until 23 June, 2011.
August 2011: A precautionary grounding of all 20 F-35s that had reached flying status was ordered Aug. 3, 2011 after a valve in the Integrated Power Package (IPP) of F-35A test aircraft AF-4 failed. On 18 August 2011 the flight ban was lifted to allow monitored operations. A permanent resolution would be installed later.
January 2012: 15 Lockheed Martin F-35s are grounded for about 12 days to repack improperly installed parachutes (reversed 180 degrees from design). The grounded aircraft are equipped with new versions of the Martin Baker US16E ejection seat, designated as -21 and -23.
January 2013: The F-35B STOVL variant was grounded Jan 18, 2013 after detection of a failure of a fueldraulic line in the aircraft's propulsion system. The Pentagon cleared all 25 F-35B aircraft to resume flight tests on February 12, 2013. Problem caused by a manufacturing quality problem (wrongly crimped fuel line).
February 2013: On Feb. 21, 2013, the Pentagon ordered a grounding for all F-35 aircraft, after a routine check at the Edwards Air Force Base revealed a crack in a low pressure turbine blade in an engines of a F-35A.
-ends-
http://www.defense-aerospace.com/articl ... blems.html
(Source: JSFNieuws.nl; published February 22, 2013)
By Johan Boeder
There have been several instances of turbine blades breaking off on the Pratt & Whitney F135 engine. Shown here are several broken blades during the first known incident, on Aug. 30, 2007, which ultimately led to the engine’s re-design in 2008. (photo P&W)
KESTEREN, Netherlands --- On Thursday, February 21, 2013, the Pentagon Friday ordered the grounding for all F-35 aircraft, after a routine check at the Edwards Air Force Base revealed a crack in a low pressure turbine blade in the engine of an F-35A.
This is but the latest incident concerning the Pratt & Whitney F135 engine, as during 2007-2009 repeated problems with turbine blades led to significant delays in the test program and a partial redesign of certain parts of the engine.
On February 19, 2013 a routine inspection took place of a Pratt & Whitney F135 engine at Edwards AFB, USA. During the inspection using a borescope, there were indications that there was a crack in a LPT turbine blade. It was confirmed after further investigation. The turbine blade is sent to Pratt & Whitney in Middletown (CT), USA for further investigation.
Statements from JSF Program Office
The F-35 JSF Program Office said in a Feb. 22 statement to the press: “It is too early to know the fleet-wide impact of this finding, however as a precautionary measure, all F-35 flight operations have been suspended until the investigation is complete and the cause of the blade crack is fully understood. The F-35 Joint Program Office is working closely with Pratt & Whitney and Lockheed Martin at all F-35 locations to ensure the integrity of the engine, and to return the fleet safely to flight as soon as possible.”
Lt. Gen. Chris Bogdan, head of the JSF Program Office, suggested in a briefing in Australia that if the crack's cause was as straightforward as a foreign object striking the turbine, or a basic manufacturing defect, “I could foresee the airplane back in the air in the next week or two.”
Bogdan added that “If it's more than that, then we have to look at what the risk is to the fleet,” adding than a verdict on the cracking's cause was expected "by the end of this week", Reuters reported from Melbourne.
Some facts about what happened
It was a F-135 engine with 700 hours, of which 409 flight hours. The aircraft was the F-35A test aircraft AF-2. The half-inch wide crack was found in a turbine blade of the low pressure turbine section. This makes it unlikely that it is caused by so-called FOD (Foreign Object Damage), such as a bird strike, because such an object has to pass the Fan Section (3 stages) Compressor Section (6 stages), combustor and high pressure turbine section before reaching the low pressure turbine section.
Cracks in turbine blades in the low pressure turbine section usually are caused by high thermal or other stressing loads of the turbine blades. The forces in the 40.000 lb (about 29.000 hp) engine are enormous. A grounding after such a discovery usually takes relatively short (e.g. one week), normally a manufacturing error or some incident is the root cause.
Until then, for safety reasons a grounding may be the standard procedure. Reuters reported Feb 24 that “In fact, two jets were airborne at air bases in Maryland and Arizona and had to be recalled, said one of the sources.” At this moment, all 51 F-35s, of all versions, in use at several airfields to support the test and training program, are grounded.
Long history of engine problems since 2006
It cannot be excluded that the root cause of the current problem is more structural than a simple manufacturing error or an isolated incident. Since 2006 there had been a series of engine problems with the F-135 engine.
In May 2006, Aviation Week reporter David A. Fulghum wrote a detailed article “Joint Strike Fighter F135 Engine Burns Hotter Than Desired” and described the risk of a shorter engine life or engine damage caused by higher than expected temperatures on the F-135 engine.
In August 2007 and February 2008 there were serious problems. Turbine blades broke off suddenly by a form of metal fatigue. The cause was sought in a combination of factors.
On 30 August 2007 in test engine FX634, after 122 hours of testing, a turbine blade in the 3rd LPT stage broke off completely. On February 4, 2008 something similar happened to engine FTE06, also in the 3rd LPT stage, after 19 hours.
These problems with the engine contributed significantly to the delays in the JSF test program for the period 2007-2008.
Redesign of the engine in 2008
In early 2008, an engine, the FX640 ground test engine, was equipped with numerous sensors and instruments. On April 21, 2008 a test process was started to find the cause of the problem. Through a detailed test plan the forces and tensions that arise in the engine were mapped in different power ranges.
At that moment it seemed to be primarily an issue of the F-35B STOVL (vertical landing) version. The cracks in the turbine blades were created in exactly the same place, and seemed to occur when switching from forward to vertical drive. Later in 2008, the results became available. The blade cracks seemed to have been caused by certain vibrations that triggered a material failure.
This led to a redesign of a number of elements in the engine. One of the upgrades was a change of the distance between the turbine blades. After the redesign the engine was retested and recertified. At the end of 2008 Pratt & Whitney issued a press statement, saying that they were convinced that the problems were solved.
(UPDATE: A link to a July 22, 2008 briefing by Pratt & Whitney on F135 blade failures was removed on Feb. 28 at the request of the F-35 Joint Program Office. The "information in those slides has the potential to compromise the safety of our pilots," the request stated -- Editor.)
In 2009, problems with redesigned engine
In July 2009, the then head of the JSF Program Office, Marine Corps Maj. Gen. David R. Heinz, was still was not happy with the F-135 problems. He told the press: “The problems include too many individual blades that fail to meet specifications, as well as combined “stack-ups” of blades that fail early. I’m not satisfied with the rates that I’m getting.”
A few days later he was ordered by the Pentagon not to comment publicly on problems with the F-135 engine.
In September 2009, serious engine problems were again revealed during testing of the Pratt & Whitney F-135 engine. At a crucial moment in the debate in the U.S. Congress on the choice of two competing engine types (the Pentagon wanted to axe the alternate engine (the GE / Rolls Royce F-136), a Pratt & Whitney F-135 engine broke down. Again, the cause seemed to lie in broken turbine blades. However, this time the same problem occurred in the new, redesigned engine with redesigned turbine blades.
Engine problems continue until now
After the problems in 2009, officials no longer publicly commented about the engine problems. Also there were no indications that there actually were problems with the engine or that there were any reliability issues.
In April 2011, however, Admiral Venlet, the then Head of JSF Program Office, told reporters that some engine problems were impacting on the delivery schedule.
The grounding last week puts the engine back in the publicity spotlight. However, this time it is not the complex F-35B STOVL version, but the much simpler engine in the F-35A, the Air Force version, that failed, which has led some observers to speculate that the problem could be more deeply ingrained in the engine’s design.
History of previous F-35 groundings
May 2007: The first incident was recorded in May 2007, when the F-35A prototype AA-1 experienced an electrical short that disabled flight controls on the horizontal stabliser. A grounding was ordered and continued until December 2007, due to time needed to redesign several parts of the 270-volt electrical system and F-135 engine problems.
July 2008: On July 23, 2008, both flying F-35 prototypes were grounded after problems were detected with ground cooling fan electrical circuitry, DCMA reported on Aug 18, 2008 that tests were delayed as a result of testing anomalies on the 28 Volt and 270 Volt Battery Charger/Controller Unit, the Electrical Distribution Unit and the Power Distribution Unit. It was due to design problems. Flights were resumed first week of September-2008.
December 2008: On Dec 12, 2008 the F-35 was grounded again as a result of engine and ejection seat anomalies. Seat anomalies were observed in ejection seat sequence during an escape system test on Nov. 20, 2008. It took nearly 3 months to solve the problems and aircraft AA-1 did not return to the skies until Feb. 24, 2009.
May 2009: The F-35 fleet didn’t fly between May 7, 2009 (84th flight of prototype AA-1) and Jun 23, 2009. No comments were available from JPO or L-M.
October 2010: F-35 fleet grounded after the fuel pump shut down above 10,000ft (3,050m). The problem was caused by a software bug.
March 2011: The entire F-35 fleet was grounded some weeks after test aircraft AF-4 experienced a dual generator failure. After both generators shut down in flight, the IPP activated and allowed the F-35’s flight control system to continue functioning. The problem was traced to faulty maintenance handling.
June 2011: Carrier-based F-35C suspended from flying after engineers at NAS Patuxent River discovered a software problem that could have affected the flight control surfaces. Grounding was from 17 June until 23 June, 2011.
August 2011: A precautionary grounding of all 20 F-35s that had reached flying status was ordered Aug. 3, 2011 after a valve in the Integrated Power Package (IPP) of F-35A test aircraft AF-4 failed. On 18 August 2011 the flight ban was lifted to allow monitored operations. A permanent resolution would be installed later.
January 2012: 15 Lockheed Martin F-35s are grounded for about 12 days to repack improperly installed parachutes (reversed 180 degrees from design). The grounded aircraft are equipped with new versions of the Martin Baker US16E ejection seat, designated as -21 and -23.
January 2013: The F-35B STOVL variant was grounded Jan 18, 2013 after detection of a failure of a fueldraulic line in the aircraft's propulsion system. The Pentagon cleared all 25 F-35B aircraft to resume flight tests on February 12, 2013. Problem caused by a manufacturing quality problem (wrongly crimped fuel line).
February 2013: On Feb. 21, 2013, the Pentagon ordered a grounding for all F-35 aircraft, after a routine check at the Edwards Air Force Base revealed a crack in a low pressure turbine blade in an engines of a F-35A.
-ends-
http://www.defense-aerospace.com/articl ... blems.html
Triste sina ter nascido português
- P44
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Re: F-35 News
USAF’s F-35A Not Even Ready for Combat Training
(Source: Project On Government Oversight; issued March 6, 2013)
Including stunning pilot comments about the aircraft's survivability (such as "Aft visibility will get the pilot gunned [down] every time"), a new, unclassified DOD document on the F-35 is now available.
It describes the performance of the F-35A and its support systems in initial training at Eglin Air Force Base in Florida. Not previously in the public domain, the unclassified DOT&E materials are available at the POGO.org.
DoT&E Memo on F-35A Operational Utility Evaluation
(Source: DoD Director, Operational Test and Evaluation; dated Feb. 15, 2013)
FOR: SECRETARY OF DEFENSE ·
FROM: J. Michael Gilmore, Director, Operational Test and Evaluation
SUBJECT: F-35A Ready For Training Operational Utility Evaluation (OUE)
• I have attached at TAB A the F-35A Ready For Training OUE Report. At the request of the Joint Strike Fighter Program Executive Officer, the OUE evaluated the capability of the F-35A air vehicle and the infrastructure at Eglin Air Force Base to train an experienced initial cadre of pilots using a very basic syllabus designed to familiarize pilots with aircraft that possessed no combat capability. It also evaluated the ability of the F-35A maintenance and Autonomic Logistics Information System to sustain a sortie generation rate consistent with the limited training contained in the Block 1 A syllabus.
In the report I conclude the following:
• The limitations, workarounds, and flight restrictions in place on the F-35A at this early stage of its development substantially limit the utility of training. However, the evaluation indicates areas where the program needs to focus attention and make improvements.
• The radar, the pilot's helmet-mounted display, and the cockpit interfaces for controlling the radios and navigational functions should be improved.
• Discrepancies between the courseware and the flight manuals were frequently observed, and the timelines to fix or update courseware should be shortened.
• The training management system lags in development compared to the rest of the Integrated Training Center and does not yet have all planned functionality.
• Plans and procedures for training pilots to recover the aircraft in the event of an engine problem or flameout should be reviewed for adequacy and to assure such training can be conducted in an appropriate venue.
• Sustainment of the six Block 1A F-35A aircraft was sufficient to meet the relatively low student training sortie demand of the syllabus, but only with substantial resources (aircraft and manpower) and workarounds to the intended sustainment system in place.
• The demonstrated reliability of the F-35A is significantly below the program office's projected targets for the reliability it expected the aircraft to achieve at the 2,500 flight hours the F-35A fleet has now accumulated.
• I am providing copies of my report to the Under Secretary of Defense for Acquisition, Technology and Logistics; the Secretary of the Air Force; the Secretary of the Navy; and the Vice Chairman of the Joint Chiefs of Staff. The professional staff of the Congressional defense committees have also requested the report and I will provide them copies next Thursday. By law, I must provide the Congress with any test-related material it requests.
Click here for the full report (68 PDF pages) on the POGO website.
(ends)
New, Unclassified DOD Document Describes F-35A Performance in Training
(Source: Project On Government Oversight; issued March 6, 2013)
(by Winslow T. Wheeler, Director, Straus Military Reform Project, POGO)
Find my summary and analysis of the document below.
The Air Force's F-35A: Not Ready for Combat, Not Even Ready for Combat Training
On February 15, 2013 the Department of Defense's Director of Operational Test and Evaluation (DOT&E) sent a memorandum and accompanying evaluation report to Congress and the DOD hierarchy describing the performance of the F-35A and its support infrastructure at Eglin Air Force Base (FL). There, already skilled Air Force pilots are undergoing a basic syllabus of familiarization training with the aircraft.
Not previously in the public domain, the unclassified DOT&E materials are available at the POGO website at http://pogoarchives.org/straus/ote-info ... 130215.pdf
DOT&E's report, titled "F-35A Joint Strike Fighter: Readiness for Training Operational Utility Evaluation," reveals yet more disappointments on the status and performance of the F-35. The Operational Utility Evaluation (OUE) is particularly valuable as it focuses on the Air Force's A model of the F-35 "Joint Strike Fighter." Many in the political and think tank world have focused more on the Marine Corps B, or Short Take Off and Vertical Landing (STOVL), version or the Navy's C model with its heavier structure and larger wings.
While the B and C are even more expensive and lower in performance-on certain key performance dimensions-than the Air Force's A model, this OUE (inadvertently) demonstrates that the A model is also flawed beyond redemption.
While the DOT&E paperwork includes an opening memo and an executive summary, they do not do justice to the detailed findings of the report. Specific issues are discussed below-much of it in quotations and showing the appropriate page number of the text of the evaluation.
RESTRICTIONS IN SOFTWARE, SYSTEMS AND FLIGHT
The currently available software essential to control the aircraft (software Blocks 1A and 1B) is "intended to provide only basic pilot training and has no combat capability. The current aircraft have a number of significant operational restrictions . such as limited maneuvering, speeds, and constrained descent rates; no carriage of weapons, no use of countermeasures, and no opening of weapons bay doors in flight." (p. 1.)
Also, ". student pilots were limited in flight maneuvering to very basic aircraft handling, such as simple turns, climbs, and descents as the flight envelope of speed and altitude was limited, angle-of-attack and g-loading were restricted, and maneuvers normally flown during a familiarization phase of a syllabus were explicitly prohibited." (p. 2.)
Table 3-1 (starting on p. 14.) outlines the many limitations. The following are prohibited:
-- Descent rates more than 6,000 feet per minute (for reference, Wikipedia shows the F-16C rate of climb to be 50,000 feet per minute);
-- Airspeed above 550 knots per hour or Mach 0.9 (not the 1.6 Mach or 1,200 mph Wikipedia says the F-35 is capable of);
-- Angle-of-attack (attitude of flight) beyond -5 and +18 degrees (e.g. not the +50 degrees the aircraft is capable of);
-- Maneuvering at more than -1 or +5 gs (nowhere near the stated +9g capability);
-- Take offs or landings in formation;
-- Flying at night or in weather;
-- Using real or simulated weapons;
-- Rapid stick or rudder movements;
-- Air-to-air or air-to-ground tracking maneuvers;
-- Refueling in the air;
-- Flying within 25 miles of lightning;
-- Use of electronic countermeasures;
-- Use of anti-jamming, secure communications, or datalink systems;
-- Electro-optical targeting;
-- Using the Distributed Aperture System of sensors to detect targets or threats;
-- Using the Identification Friend or Foe (IFF) Interrogator;
-- Using the helmet mounted display system as a "primary reference;"
-- Use of air-to-air or air-to-ground radar modes for electronic attack, sea search, ground-moving targets or close-in air combat modes. (pp. 14-16.)
In addition, "...the radar system exhibited shortfalls that - if not corrected - may significantly degrade the ability to train and fly safely under a typical transition training syllabus, where an operational radar is required. The radar performance shortfalls ranged from the radar being completely inoperative on two sorties to failing to display targets on one sortie, inexplicably dropping targets on another sortie, and taking excessive time to develop a track on near co-speed targets on yet another sortie." (p. 13.)
"AFT VISIBILITY WILL GET THE PILOT GUNNED EVERY TIME"
A key system of the aircraft, the pilot's multi-million dollar helmet-mounted display (HMD) of the aircraft's operating systems, threats, targets and other information "functioned more or less adequately. [but] presented frequent problems for the pilots."
These included "misalignment of the virtual horizon display with the actual horizon, inoperative or flickering displays, and focal problems - where the pilot would have either blurry or 'double vision' in the display. The pilots also mentioned problems with stability, jitter, latency, and brightness of the presentation in the helmet display.." Two of the complaints were basically that elements of the helmet made it harder, not easier, to see outside the aircraft. (pp. 16-17.)
There are additional problems for detecting threats in the all-important visual mode: the ejection seat headrest and canopy "bow" (where the canopy meets the fuselage) are designed in such a way as to impede seeing aircraft to the rear: one pilot commented "A pilot will find it nearly impossible to check [their six o'clock position{to the rear}] under g." Another commented, "The head rest is too large and will impede aft visibility and survivability during surface and air engagements," and "Aft visibility will get the pilot gunned [down] every time," referring to close-range combat. (p. 18.)
Indeed, DOT&E stated explicitly "The out-of-cockpit visibility in the F-35 is less than other Air Force fighter aircraft." (p. 17.)
To summarize in different words, the helmet-mounted display and the F-35 system does not present an enhanced, clearer view of the outside world, targets and threats to the pilot; instead, they present a distorted and/or obstructed view.
This is one of the most serious backward steps that the entire F-35 system takes, and it presents an even greater threat to the survivability of the F-35 and its pilot than the astounding evidence of the flammability of the F-35 (all versions) in the recent analysis of another DOT&E report by military analyst Lee Gaillard at Counterpunch at http://www.counterpunch.org/2013/03/04/ ... -the-f-35/
In the event of the pilot needing to escape from the aircraft, there are also some incompletely explained problems with the ejection seat in "off-normal" situations, i.e. those that can occur in combat or even real training. (p. 43.)
SUSTAINMENT
While there is little that is more important than pilot and aircraft survivability, additional, almost-as stunning revelations about the F-35A involved its "sustainment"-or reliability, maintainability, and availability.
While the report states "Sustainment of the six Block 1A F-35A aircraft was sufficient to meet the student training sortie requirements of the syllabus" (p. ii.), it further explains that this was despite "generous" Air Force resources and a "hybrid of government and contractor support personnel that relies heavily on workaround procedures, non-standard support procedure, and specialized support equipment to generate sorties and maintain the F-35A fleet.." (p. iv).
Moreover, "the program is not meeting reliability growth targets.." That is to say, it is not as reliable as it should be for this stage of its development. (pp. iv and 27) It is also important to note that this was despite the aircraft lacking many mission systems "which resulted in far fewer failure modes and a narrower scope of demand on the supply chain" than would a combat capable aircraft. (In other words, had more of the F-35's complex components and systems been available for use, the aircraft would have required still more maintenance, with the commensurate, additional loss of reliability and availability. [p. 27])
The as is sustainment numbers were not impressive.
The F-35 program required an air abort rate no greater than 1,000 aborts per 100,000 flight hours to commence F-35A training (p. 27): while they were previously even higher, in late 2012-well after the training started-the aircraft had an air abort rate of 3,600 air aborts per 100,000 flying hours. (p. 28)
Mission aborts while the plane is still on the ground (ground aborts) were also a serious problem: one in seven sortie attempts resulted in a ground abort. (p. 28)
The Air Force wanted the F-35As at Eglin AFB to be available for training missions 33 percent of the time: the equivalent of each aircraft flying one sortie every three days. (pp. 29, 30) By late 2012 this very modest minimum was basically being achieved (p. 29), but certain aircraft at various times during the OUE flew as seldom as one sortie every 7 to 10 days. (pp. 30, 31)
Mean Flight Hours Between Critical Failures (a typical measure of reliability) occurred every four hours, on average-well short of the expected 11 hours at this stage of the F-35's development-and well below the aircraft's ultimate goal of a modest 20 hours. (p. 34) The F-35As at Eglin also failed reliability goals for this stage of development: a major problem was the poor reliability of the complicated, badly performing helmet. (p. 34)
Similar problems occurred on the maintenance time the aircraft required. (pp. 36, 37) For example, the mean elapsed time for an engine removal and installation was 52 hours; the system threshold is 120 minutes. (p. 37)
One component vividly demonstrated the fragility of the F-35A. Temperatures at Eglin as moderate as <59 degrees Fahrenheit caused a problem for the 270 Volt Battery Charger Control Unit inside the airplane. Maintainers had to warm the aircraft in hangars overnight to prevent ground aborts. (p. 38) Foreign purchasers such as Canada and Norway, already wary of real cold weather issues for their F-35As, are sure to be concerned with a "cold weather" issue at just 59 degrees and below.
The aircraft's Autonomic Logistics Information System (ALIS) was limited and required workarounds throughout the operating cycle (p. 38), and it has potential problems in hot weather when air conditioning is not available, which would cause ALIS to shut down altogether. The system was also cumbersome and time consuming. (pp. 39-41)
CONCLUSION
The conclusion is obvious: The F-35A is not viable.
(EDITOR’S NOTE: Not mentioned above, but reported by the Toronto Star, are two other points:
-- “Mechanics have had their own gripes. It takes more than two days to swap out an engine rather than the two hours it was supposed to take.
-- “And because a battery unit is vulnerable in cool temperatures, ground crews have had to keep the aircraft in heated hangars overnight, taking up space that would otherwise be used for jets needing repairs. “Moving jets in and out of a hangar to keep them warm involves five personnel for three to four hours per shift,” the report says, or 15 to 20 man-hours.)
-ends-
http://www.defense-aerospace.com/articl ... mance.html
(Source: Project On Government Oversight; issued March 6, 2013)
Including stunning pilot comments about the aircraft's survivability (such as "Aft visibility will get the pilot gunned [down] every time"), a new, unclassified DOD document on the F-35 is now available.
It describes the performance of the F-35A and its support systems in initial training at Eglin Air Force Base in Florida. Not previously in the public domain, the unclassified DOT&E materials are available at the POGO.org.
DoT&E Memo on F-35A Operational Utility Evaluation
(Source: DoD Director, Operational Test and Evaluation; dated Feb. 15, 2013)
FOR: SECRETARY OF DEFENSE ·
FROM: J. Michael Gilmore, Director, Operational Test and Evaluation
SUBJECT: F-35A Ready For Training Operational Utility Evaluation (OUE)
• I have attached at TAB A the F-35A Ready For Training OUE Report. At the request of the Joint Strike Fighter Program Executive Officer, the OUE evaluated the capability of the F-35A air vehicle and the infrastructure at Eglin Air Force Base to train an experienced initial cadre of pilots using a very basic syllabus designed to familiarize pilots with aircraft that possessed no combat capability. It also evaluated the ability of the F-35A maintenance and Autonomic Logistics Information System to sustain a sortie generation rate consistent with the limited training contained in the Block 1 A syllabus.
In the report I conclude the following:
• The limitations, workarounds, and flight restrictions in place on the F-35A at this early stage of its development substantially limit the utility of training. However, the evaluation indicates areas where the program needs to focus attention and make improvements.
• The radar, the pilot's helmet-mounted display, and the cockpit interfaces for controlling the radios and navigational functions should be improved.
• Discrepancies between the courseware and the flight manuals were frequently observed, and the timelines to fix or update courseware should be shortened.
• The training management system lags in development compared to the rest of the Integrated Training Center and does not yet have all planned functionality.
• Plans and procedures for training pilots to recover the aircraft in the event of an engine problem or flameout should be reviewed for adequacy and to assure such training can be conducted in an appropriate venue.
• Sustainment of the six Block 1A F-35A aircraft was sufficient to meet the relatively low student training sortie demand of the syllabus, but only with substantial resources (aircraft and manpower) and workarounds to the intended sustainment system in place.
• The demonstrated reliability of the F-35A is significantly below the program office's projected targets for the reliability it expected the aircraft to achieve at the 2,500 flight hours the F-35A fleet has now accumulated.
• I am providing copies of my report to the Under Secretary of Defense for Acquisition, Technology and Logistics; the Secretary of the Air Force; the Secretary of the Navy; and the Vice Chairman of the Joint Chiefs of Staff. The professional staff of the Congressional defense committees have also requested the report and I will provide them copies next Thursday. By law, I must provide the Congress with any test-related material it requests.
Click here for the full report (68 PDF pages) on the POGO website.
(ends)
New, Unclassified DOD Document Describes F-35A Performance in Training
(Source: Project On Government Oversight; issued March 6, 2013)
(by Winslow T. Wheeler, Director, Straus Military Reform Project, POGO)
Find my summary and analysis of the document below.
The Air Force's F-35A: Not Ready for Combat, Not Even Ready for Combat Training
On February 15, 2013 the Department of Defense's Director of Operational Test and Evaluation (DOT&E) sent a memorandum and accompanying evaluation report to Congress and the DOD hierarchy describing the performance of the F-35A and its support infrastructure at Eglin Air Force Base (FL). There, already skilled Air Force pilots are undergoing a basic syllabus of familiarization training with the aircraft.
Not previously in the public domain, the unclassified DOT&E materials are available at the POGO website at http://pogoarchives.org/straus/ote-info ... 130215.pdf
DOT&E's report, titled "F-35A Joint Strike Fighter: Readiness for Training Operational Utility Evaluation," reveals yet more disappointments on the status and performance of the F-35. The Operational Utility Evaluation (OUE) is particularly valuable as it focuses on the Air Force's A model of the F-35 "Joint Strike Fighter." Many in the political and think tank world have focused more on the Marine Corps B, or Short Take Off and Vertical Landing (STOVL), version or the Navy's C model with its heavier structure and larger wings.
While the B and C are even more expensive and lower in performance-on certain key performance dimensions-than the Air Force's A model, this OUE (inadvertently) demonstrates that the A model is also flawed beyond redemption.
While the DOT&E paperwork includes an opening memo and an executive summary, they do not do justice to the detailed findings of the report. Specific issues are discussed below-much of it in quotations and showing the appropriate page number of the text of the evaluation.
RESTRICTIONS IN SOFTWARE, SYSTEMS AND FLIGHT
The currently available software essential to control the aircraft (software Blocks 1A and 1B) is "intended to provide only basic pilot training and has no combat capability. The current aircraft have a number of significant operational restrictions . such as limited maneuvering, speeds, and constrained descent rates; no carriage of weapons, no use of countermeasures, and no opening of weapons bay doors in flight." (p. 1.)
Also, ". student pilots were limited in flight maneuvering to very basic aircraft handling, such as simple turns, climbs, and descents as the flight envelope of speed and altitude was limited, angle-of-attack and g-loading were restricted, and maneuvers normally flown during a familiarization phase of a syllabus were explicitly prohibited." (p. 2.)
Table 3-1 (starting on p. 14.) outlines the many limitations. The following are prohibited:
-- Descent rates more than 6,000 feet per minute (for reference, Wikipedia shows the F-16C rate of climb to be 50,000 feet per minute);
-- Airspeed above 550 knots per hour or Mach 0.9 (not the 1.6 Mach or 1,200 mph Wikipedia says the F-35 is capable of);
-- Angle-of-attack (attitude of flight) beyond -5 and +18 degrees (e.g. not the +50 degrees the aircraft is capable of);
-- Maneuvering at more than -1 or +5 gs (nowhere near the stated +9g capability);
-- Take offs or landings in formation;
-- Flying at night or in weather;
-- Using real or simulated weapons;
-- Rapid stick or rudder movements;
-- Air-to-air or air-to-ground tracking maneuvers;
-- Refueling in the air;
-- Flying within 25 miles of lightning;
-- Use of electronic countermeasures;
-- Use of anti-jamming, secure communications, or datalink systems;
-- Electro-optical targeting;
-- Using the Distributed Aperture System of sensors to detect targets or threats;
-- Using the Identification Friend or Foe (IFF) Interrogator;
-- Using the helmet mounted display system as a "primary reference;"
-- Use of air-to-air or air-to-ground radar modes for electronic attack, sea search, ground-moving targets or close-in air combat modes. (pp. 14-16.)
In addition, "...the radar system exhibited shortfalls that - if not corrected - may significantly degrade the ability to train and fly safely under a typical transition training syllabus, where an operational radar is required. The radar performance shortfalls ranged from the radar being completely inoperative on two sorties to failing to display targets on one sortie, inexplicably dropping targets on another sortie, and taking excessive time to develop a track on near co-speed targets on yet another sortie." (p. 13.)
"AFT VISIBILITY WILL GET THE PILOT GUNNED EVERY TIME"
A key system of the aircraft, the pilot's multi-million dollar helmet-mounted display (HMD) of the aircraft's operating systems, threats, targets and other information "functioned more or less adequately. [but] presented frequent problems for the pilots."
These included "misalignment of the virtual horizon display with the actual horizon, inoperative or flickering displays, and focal problems - where the pilot would have either blurry or 'double vision' in the display. The pilots also mentioned problems with stability, jitter, latency, and brightness of the presentation in the helmet display.." Two of the complaints were basically that elements of the helmet made it harder, not easier, to see outside the aircraft. (pp. 16-17.)
There are additional problems for detecting threats in the all-important visual mode: the ejection seat headrest and canopy "bow" (where the canopy meets the fuselage) are designed in such a way as to impede seeing aircraft to the rear: one pilot commented "A pilot will find it nearly impossible to check [their six o'clock position{to the rear}] under g." Another commented, "The head rest is too large and will impede aft visibility and survivability during surface and air engagements," and "Aft visibility will get the pilot gunned [down] every time," referring to close-range combat. (p. 18.)
Indeed, DOT&E stated explicitly "The out-of-cockpit visibility in the F-35 is less than other Air Force fighter aircraft." (p. 17.)
To summarize in different words, the helmet-mounted display and the F-35 system does not present an enhanced, clearer view of the outside world, targets and threats to the pilot; instead, they present a distorted and/or obstructed view.
This is one of the most serious backward steps that the entire F-35 system takes, and it presents an even greater threat to the survivability of the F-35 and its pilot than the astounding evidence of the flammability of the F-35 (all versions) in the recent analysis of another DOT&E report by military analyst Lee Gaillard at Counterpunch at http://www.counterpunch.org/2013/03/04/ ... -the-f-35/
In the event of the pilot needing to escape from the aircraft, there are also some incompletely explained problems with the ejection seat in "off-normal" situations, i.e. those that can occur in combat or even real training. (p. 43.)
SUSTAINMENT
While there is little that is more important than pilot and aircraft survivability, additional, almost-as stunning revelations about the F-35A involved its "sustainment"-or reliability, maintainability, and availability.
While the report states "Sustainment of the six Block 1A F-35A aircraft was sufficient to meet the student training sortie requirements of the syllabus" (p. ii.), it further explains that this was despite "generous" Air Force resources and a "hybrid of government and contractor support personnel that relies heavily on workaround procedures, non-standard support procedure, and specialized support equipment to generate sorties and maintain the F-35A fleet.." (p. iv).
Moreover, "the program is not meeting reliability growth targets.." That is to say, it is not as reliable as it should be for this stage of its development. (pp. iv and 27) It is also important to note that this was despite the aircraft lacking many mission systems "which resulted in far fewer failure modes and a narrower scope of demand on the supply chain" than would a combat capable aircraft. (In other words, had more of the F-35's complex components and systems been available for use, the aircraft would have required still more maintenance, with the commensurate, additional loss of reliability and availability. [p. 27])
The as is sustainment numbers were not impressive.
The F-35 program required an air abort rate no greater than 1,000 aborts per 100,000 flight hours to commence F-35A training (p. 27): while they were previously even higher, in late 2012-well after the training started-the aircraft had an air abort rate of 3,600 air aborts per 100,000 flying hours. (p. 28)
Mission aborts while the plane is still on the ground (ground aborts) were also a serious problem: one in seven sortie attempts resulted in a ground abort. (p. 28)
The Air Force wanted the F-35As at Eglin AFB to be available for training missions 33 percent of the time: the equivalent of each aircraft flying one sortie every three days. (pp. 29, 30) By late 2012 this very modest minimum was basically being achieved (p. 29), but certain aircraft at various times during the OUE flew as seldom as one sortie every 7 to 10 days. (pp. 30, 31)
Mean Flight Hours Between Critical Failures (a typical measure of reliability) occurred every four hours, on average-well short of the expected 11 hours at this stage of the F-35's development-and well below the aircraft's ultimate goal of a modest 20 hours. (p. 34) The F-35As at Eglin also failed reliability goals for this stage of development: a major problem was the poor reliability of the complicated, badly performing helmet. (p. 34)
Similar problems occurred on the maintenance time the aircraft required. (pp. 36, 37) For example, the mean elapsed time for an engine removal and installation was 52 hours; the system threshold is 120 minutes. (p. 37)
One component vividly demonstrated the fragility of the F-35A. Temperatures at Eglin as moderate as <59 degrees Fahrenheit caused a problem for the 270 Volt Battery Charger Control Unit inside the airplane. Maintainers had to warm the aircraft in hangars overnight to prevent ground aborts. (p. 38) Foreign purchasers such as Canada and Norway, already wary of real cold weather issues for their F-35As, are sure to be concerned with a "cold weather" issue at just 59 degrees and below.
The aircraft's Autonomic Logistics Information System (ALIS) was limited and required workarounds throughout the operating cycle (p. 38), and it has potential problems in hot weather when air conditioning is not available, which would cause ALIS to shut down altogether. The system was also cumbersome and time consuming. (pp. 39-41)
CONCLUSION
The conclusion is obvious: The F-35A is not viable.
(EDITOR’S NOTE: Not mentioned above, but reported by the Toronto Star, are two other points:
-- “Mechanics have had their own gripes. It takes more than two days to swap out an engine rather than the two hours it was supposed to take.
-- “And because a battery unit is vulnerable in cool temperatures, ground crews have had to keep the aircraft in heated hangars overnight, taking up space that would otherwise be used for jets needing repairs. “Moving jets in and out of a hangar to keep them warm involves five personnel for three to four hours per shift,” the report says, or 15 to 20 man-hours.)
-ends-
http://www.defense-aerospace.com/articl ... mance.html
Triste sina ter nascido português
- cabeça de martelo
- Sênior
- Mensagens: 39444
- Registrado em: Sex Out 21, 2005 10:45 am
- Localização: Portugal
- Agradeceu: 1136 vezes
- Agradeceram: 2843 vezes
- NovaTO
- Sênior
- Mensagens: 1251
- Registrado em: Dom Set 06, 2009 10:37 pm
- Agradeceu: 5 vezes
- Agradeceram: 47 vezes
Re: F-35 News
Se cancelarem esse programa, tem a USAF/Marines/USNavy terem os US$ bilhões investidos de volta? Porque se não, acho difícil cancelar algo dessa monta.
[]'s
[]'s
- P44
- Sênior
- Mensagens: 55236
- Registrado em: Ter Dez 07, 2004 6:34 am
- Localização: O raio que vos parta
- Agradeceu: 2750 vezes
- Agradeceram: 2429 vezes
Re: F-35 News
NovaTO escreveu:Se cancelarem esse programa, tem a USAF/Marines/USNavy terem os US$ bilhões investidos de volta? Porque se não, acho difícil cancelar algo dessa monta.
[]'s
Também não acredito num cancelamento desse chasso... há muita coisa envolvida, a começar no prestigio...vão torrar biliões e biliões nessa carroça-topo-de-gama só para dizerem que é o supra-sumo que torrem, que torrem...
Triste sina ter nascido português
- Penguin
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- Mensagens: 18983
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- Agradeceu: 5 vezes
- Agradeceram: 374 vezes
Re: F-35 News
Perderão todo o dinheiro e tempo investido até agora (+US$50 bi).NovaTO escreveu:Se cancelarem esse programa, tem a USAF/Marines/USNavy terem os US$ bilhões investidos de volta? Porque se não, acho difícil cancelar algo dessa monta.
[]'s
Sempre e inevitavelmente, cada um de nós subestima o número de indivíduos estúpidos que circulam pelo mundo.
Carlo M. Cipolla
Carlo M. Cipolla
- J.Ricardo
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Re: F-35 News
E Portugal que se cuide, daqui uns anos a validade dos F-16 vence, e qual avião você acha que vão comprar???P44 escreveu:NovaTO escreveu:Se cancelarem esse programa, tem a USAF/Marines/USNavy terem os US$ bilhões investidos de volta? Porque se não, acho difícil cancelar algo dessa monta.
[]'s
Também não acredito num cancelamento desse chasso... há muita coisa envolvida, a começar no prestigio...vão torrar biliões e biliões nessa carroça-topo-de-gama só para dizerem que é o supra-sumo que torrem, que torrem...
Não temais ímpias falanges,
Que apresentam face hostil,
Vossos peitos, vossos braços,
São muralhas do Brasil!
Que apresentam face hostil,
Vossos peitos, vossos braços,
São muralhas do Brasil!
- P44
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Re: F-35 News
Ah, o nosso governo até já se está querendo livrar dos F-16, acha que eles estão preocupados com isso???J.Ricardo escreveu:E Portugal que se cuide, daqui uns anos a validade dos F-16 vence, e qual avião você acha que vão comprar???P44 escreveu:
Também não acredito num cancelamento desse chasso... há muita coisa envolvida, a começar no prestigio...vão torrar biliões e biliões nessa carroça-topo-de-gama só para dizerem que é o supra-sumo que torrem, que torrem...
Os F-16 vão voar até cairem que nem tordos (á lá A7-P), depois nossos generosos "aliados" EUA nos fornecerão qualquer coisa que esteja estocada no deserto do Mojave.
De qq maneira, F-35 seria sempre muita areia para a nossa camioneta, Portugal não tem possibilidade de ter um avião desse custo nem nunca terá.
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