I don't understand it all but apparently the story is: (a) When the F35 was designed, it reduced the number of external air scoops by using integrated heat exch

I don't understand it all but apparently the story is: (a) When the F35 was designed, it reduced the number of external air scoops by using integrated heat exchangers which used the relative cool air from the engine fan (the first stage of the engine) to cool all the plane's systems [1]. Bleed air is when you "bleed" or tap the exhaust of the engine and use it to power other systems i.e., power the system that produces electricity. The GAO says this design is flawed. To make up for it, pilots have run the engines harder/hotter. Which reduces the life of the engines [2]. The GAO said Lockheed told P&W five years after the program started, it needed more bleed air. Based on our preliminary observations, the PTMS needs more air pressure from the engine to cool subsystems than originally anticipated, which means that the engine is working harder than it was designed to, resulting in reduced engine life. Program officials explained that Pratt & Whitney designed the engine to provide a certain amount of air pressure to the PTMS, which Lockheed Martin defined early in the development program. While Pratt & Whitney’s F135 engine met those specifications, program officials stated that in 2008, Lockheed Martin discovered that the PTMS would need more air pressure from the engine than originally anticipated to help cool aircraft subsystems. According to program officials, in 2013, Lockheed Martin requested to change the F135’s design to provide more air pressure to the PTMS, but program officials determined that it was too late to redesign the engine given the cost and schedule impacts of such a change at that stage of the overall program. Program officials decided to continue with the F135 engine’s original design with the understanding that there would be increased wear and tear on the engine because it would need to provide more air pressure to the PTMS than its design intended. However, the higher air pressure needs results in the engine working harder than intended, which increases maintenance and reduces engine life. As we reported in July 2022, the engine is witnessing higher than expected maintenance Furthermore, the USAF plans to upgrade the F35 with its new TRS3 computer system to field Block 4 capabilities which will require even more electrical power which will generate even more waste heat etc [3]. TR-3 provides computational horsepower to support Block 4 modernization capabilities. Block 4 upgrades add new and enhanced capabilities to ensure our platform remains relevant against rapidly evolving threats. The existing infrastructure relies on ten-year-old processing and memory, which cannot fully unlock the new capabilities needed for warfighter success. Much like a new mobile cell phone or personal computer, TR-3 will host new Block 4 capabilities and applications with significantly more computing power and memory than the legacy infrastructure. [1] https://www.codeonemagazine.com/article.html?item_id=28 https://www.codeonemagazine.com/article.html?item_id=28 [2] https://armedservices.house.gov/sites/republicans.armedservices.house.gov/files/Ludwigson%20Statement.pdf https://armedservices.house.gov/sites/republicans.armedservi... [3] https://armedservices.house.gov/sites/republicans.armedservices.house.gov/files/Schmidt%20Testimony.pdf https://armedservices.house.gov/sites/republicans.armedservi...