Истребитель F-35

РС
чта за пятна перед линзой? пальцы в масле?
Наверно пятна. Вообще странный борт - это видимо тренировочный, в том числе и для техников, т.к. ни одна из сервисных панелей не зашпаклевана по швам. Видимо для экономии их просто откручивают прикручивают на место. А эти панели рядом с линзами вообще похоже просто откидываются наверх, освобождая место обслуживания двигателя.
 
А вот это плохая новость:
Речь только про сверхзвук на форсаже. F-35 на сверхзвуковой скорости может и без форсажа лететь. Всё равно плохо, но хоть не исключает сверхзвук как таковой, и даже дает немного дожигателем пользоваться.
Я только не понял, это всё касается исключительно С и В моделей?
 
Речь только про сверхзвук на форсаже. F-35 на сверхзвуковой скорости может и без форсажа лететь. Всё равно плохо, но хоть не исключает сверхзвук как таковой, и даже дает немного дожигателем пользоваться.
Я только не понял, это всё касается исключительно С и В моделей?
Почитал прошлогоднюю статью, на которую они ссылаются.


Да, это только для версий B и C. Проблемы касаются скоростей 1,2 М и выше, а это все-таки с форсажем.

For example, an F-35C can only fly at Mach 1.3 in afterburner for 50 cumulative seconds, meaning that a pilot cannot clock 50 seconds at that speed, slow down for a couple seconds and then speed back up. However, the time requirements reset after the pilot operates at military power — an engine power setting that allows for less speed and thrust than afterburner — for a duration of three minutes.

The F-35B can fly for 80 cumulative seconds at Mach 1.2 or 40 seconds at Mach 1.3 without risking damage.
Но есть нюансы:
Both deficiencies were first observed in late 2011 following flutter tests where the F-35B and F-35C both flew at speeds of Mach 1.3 and Mach 1.4.

Vice Adm. Mat Winter, who leads the F-35 program on behalf of the Pentagon, told Defense News that the department has taken steps to mitigate the problem with an improved spray-on coating, but added that the government will not completely fix it — instead accepting additional risk.

As justification for the decision, Winter noted that the issue was documented while the jet was flying at the very edge of its flight envelope. He also said the phenomenon only occurred once for both the B and C models, despite numerous attempts to replicate the conditions that caused the problem.
Эта проблема была зафиксирована всего два раза, по разу на каждой модели в 2011 году. С тех пор и покрытие уже улучшали, и делали многочисленные попытки повторить это в аналогичных условиях, но больше проблемы не возникало.

И вероятность повторения этого события оценивается так:

“How often do we expect something like that to occur?” he said. “It's very, very small.”
Greg Ulmer, Lockheed Martin’s F-35 program head, said there have been no cases of this problem occurring in the operational fleet and that incidents have been limited to the “highest extremes of flight testing conditions that are unlikely replicated in operational scenarios.”
И комментарий одного из летчиков:

However, a naval aviator currently in service said the afterburner problem may not be that troubling to pilots, who must frequently work around a jet’s limitations. The key, he said, is understanding how often the issue occurs.

"I think you'd do well to go back and look at all the times they used the afterburner and that didn't happen," he said. "We're talking about tens of thousands of sorties at this point that this aircraft has flown."

Other aircraft that the Navy operates also have afterburner limits, he explained.

“I think that number needs context,” he said. "It looks scary on its own, but [the Super Hornet] has afterburner limits. They’re not that restrictive, but they have them. The aircraft has an afterburner, you want it to work.

“But I would want to get context for that number: Does this represent 0.002 percent of all sorties? If that’s the case, I don’t give a sh--, and I’ll probably have 15 other things fail before that."
В целом, это весьма редкая проблема, наблюдавшаяся пару раз почти 10 лет назад. Покрытие уже модифицировали, полеты на больших скоростях протестировали, больше проблема не проявлялась. Но так как точных причин этих проблем не нашли и не могут гарантировать, что вероятность их появления равна нулю при длительном полете, то на всякий случай запретили долго летать на больших скоростях без крайней необходимости. Как пишут в статье “break glass in case of emergency”.
 
In June 2019, Defense News published an investigation delving into the details of 13 previously unreported category 1 deficiencies — the designation given to major flaws that impact safety or mission effectiveness.
Following the report, five of those 13 category 1 problems have been “closed,” meaning they were eliminated or sufficiently corrected. Five were downgraded to a lower level of deficiency after actions were taken to help mitigate negative effects, and three issues remain open and unsolved, according to the F-35 program executive office.
Four additional CAT 1 problems have also since been added to the list, raising the total CAT 1 deficiencies to seven. The program office declined to provide additional details about those issues for classification reasons, but stated that software updates should allow all of them to be closed by the end of 2020.
...Aside from four classified problems, there remain three open category 1 deficiencies in need of a fix...

Spikes in the F-35 cockpit’s cabin pressure have been known to cause barotrauma, or extreme ear and sinus pain.

...
On nights with little starlight, the night vision camera sometimes displays green striations that make it difficult for all F-35 variants to see the horizon or to land on ships.
On nights where there is little ambient light, horizontal green lines sometimes appear on the night vision camera feed, obscuring the horizon and making landing on a ship more dangerous.
The problem is different than the notorious “green glow” issue, caused when the F-35 helmet-mounted display’s LED lights produce a greenish luminescence that inhibits a pilot’s ability to land on an aircraft carrier on nights with very little light.
At one point, both Lockheed and the government’s program office believed both problems could be solved by the F-35 Generation III helmet that the U.S. military began fielding last year.
Although the program office no longer considers the “green glow” problem a deficiency, it appears that the new helmet did not completely solve the night vision camera issue. The program office told Defense News that it intends to develop software improvements and test them in flight later this year, but the deficiency will not be considered “closed” until at least 2021.

The sea search mode of the F-35’s radar only illuminates a small slice of the sea’s surface.
...Although this problem can be fixed with software modifications and an upgrade to the radar’s processing power, it will continue to be on the books for some time. According to the program office, “[the] U.S. services agreed to plan for an improved radar mode, which will require the Technology Refresh-1 avionics update, for software release in [calendar year] 2024.”
 
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