Flight Lieutenant Alex Parr died in July 2016 (Picture: MOD).
Experienced RAF crew noticed problems with a plane just days before it suffered an engine failure and crashed killing an RAF test pilot, an inquest heard.
Flight Lieutenant Alex Parr died when the Yak-52 civilian aircraft crashed during an emergency landing close to Dinton Airfield in Wiltshire in July 2016.
Some pilots and flight engineers, undergoing high-level training at the Empire Test Pilots' School, discussed the "unserviceability" of the plane with some of the instruments not working.
But the inquest in Salisbury heard that these concerns were not reported to staff who ran the school at MOD Boscombe Down.
Flight Lieutenant Jim Goodship, an RAF engineer, was taken up in the Yak-52 by civilian pilot John Calverley just days before Flight Lieutenant Parr was killed.
He said he was in the rear seat of the plane and he noticed the RPM gauge, gyro horizon gauge and compass in his cockpit were not working as they taxied up the runway.
"I can't remember his exact words but the impression I got was that his instruments were working," Flight Lieutenant Goodship said.
The witness said he did not know whether the instruments in the front and rear cockpits were directly linked or not.
"It would have caused me more of a concern. I would have questioned it a lot more. I would have wanted to satisfy myself a little that he was capable of setting the RPM himself," he said.
"Without the benefit of hindsight I would have continued the sortie. Everything else I was content with."
Flight Lieutenant Goodship was asked why he had not reported the faulty instruments, and he replied: "I assumed it may have been raised by someone else.
"At that particularly point in the course, I was probably struggling and I was under a lot of pressure."
John Cooper QC, representing Flight Lieutenant Parr's widow Alice, asked him whether he thought there was "complacency" at the training school.
"At the time I do not. At the time I would not have said there was a complacent attitude," he replied.
He also rejected the suggestion that by raising concerns about the plane he would be seen as "pedantic or a worrier".
Flight Lieutenant Leo Cheng and Flight Lieutenant Giles Croft, both training to be a test pilot, said students were informed that some instruments were not working.
Flight Lieutenant Croft said: "I was comfortable proceeding with the sortie which is why I got into the plane that day."
Flight Lieutenant Parr was a passenger in the Yak-52 with Mr Calverley as the pilot in charge and safety pilot.
The two-seater plane was privately owned but sub-contracted to Qinetiq who ran the school on behalf of the MOD.
The court heard the Yak-52 was used in instruction flights to train elite pilots to become test pilots and instructors.