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Kip:

Not from a manual but I worked in a test flight environment for several years.

Test Flights are flights that are taken with an aircraft or system that has NEVER been used in flight. Like a new aircraft type.

Validation and verification flights are taken to ensure an existing system functions correctly and can only be tested in flight.

Very few airlines ever need to conduct a test flight.

It is terminology that people are hung up on. There is language in the CARS in this regard but frankly I am too lazy (vacation) to look it up.

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Ok, Thanks.

I'm not familiar with the notation of a "test" flight in the airline industry but I do know that in the CF Mil, any flight labelled as a "test" flight had to be flown by a very experienced pilot on that aircraft type. Normally theses test flights would have the aircraft flown to the limits of the flight envelope and at times just beyond the limits especially if the item that was fixed/changed was important to the safety of man and machine. .

In some of the whiz-bang squadrons we had dedicated test flight pilots who did the acceptance flight for any and all aircraft that had had a major overhaul or flight characteristic change. Again these were the most experienced pilots on that particular aircraft type.

Validation and verification flights are taken to ensure an existing system functions correctly and can only be tested in flight.

Agree....these simple flights were normally done by "qualified on type" pilots but validation and verification flights never put man and machine in a tenuous situation should there be a failure of the equipment being tested.

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If your airline is returning an aircraft to the lessor or if they are taking on a lease or purchase of a used aircraft, then chances are very high that an acceptance test flight (like the one being done by the ANZ crew in France) will be required. There are elements of that flight profile that take the aircraft out of the normal range and for that reason, they must be flown with great care.

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Upset events during maintenance test flights are frequent enough, usually a consequence of inputs, or oversights by the inexperienced newly minted ‘test pilot’ and a process that has thankfully become more restrictive over time.

The industry has learned from experience and has moved to limit line pilots to conducting low risk test activities; I think fixed gear down ferries are now off the line pilot’s list of test flight activities for instance. Troubleshooting is becoming ever more restrictive too and is generally limited to issues that will have absolutely no implication on continuing safe stable flight.

Practice has proven that the average aviator, no matter how much time he has on type, lacks the necessary technical expertise and appreciation for aircraft systems to ‘safely’ conduct ‘test flights, never mind the fact he typically has zero practical training / experience in the know how related to recovery from unusual attitudes etc..

If my recollection is correct, the aircraft Commander in the recent Air Asia A320 crash had considerable experience on type. It would seem he was perhaps over confident in his appreciation of aircraft systems though, which appears to have led him to take the aircraft into a realm where only true test pilots properly belong. Someone else mentioned another 320 loss above that too occurred on a maintenance test flight that everyone involved no doubt thought was going to be routine.

As it is, excepting military experienced pilots, very few ATP’s have ever been exposed to inverted flight, let alone aerobatic manoeuvres, which can easily be the unintended result when things go horribly wrong during maintenance test flights?

How many maintenance test flights are carried out with pilots trained and experienced at recovering swept-wing transport aircraft from severe upsets? The short answer is ... almost none.

If one was to take a serious look at the amount, degree and intensity of training that goes into qualifying a real test pilot it’s fairly easy to see how dangerously limited the tool kit is of the average line pilot in this regard.

Experience is critical to the type of flight activity undertaken. For example; even though I’m pretty sure neither Kip, nor Rich are test pilots, I would sure feel a heck of a lot better being upside down unexpectedly with one of these guys at the helm specifically because of their unique training & experience than I ever could be with someone that’s come up through the college programs and the like that has to try and figure the situation out for the first time and react properly.

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If your comment is directed my way JO I should clarify as my comment was not intended as a ‘slam’ against management pilots, but more of a necessary inclusion.

I’ve seen flight ops policy amendments that prohibit line pilots from flying fixed gear down ferries for instance, but ‘specifically’ allow management training & check pilots to fly the mission, which is at a minimum, a questionable practice. I mean, who wants to fly an aircraft in that state anyway, but for anyone to suggest the danger factor is somehow alleviated because a management pilot is flying is a little presumptuous I think.

As you’re aware, management pilots, trainers and checkers are not anymore qualified that a line pilot might be in respect of their test pilot qualifications; on balance they are as often as not, less experienced and current on type than the guy flying the line. I specifically highlighted management pilots to avoid the confusion that might arise if non-pilots were to assume a management type pilot has special qualifications in this respect.

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I have been involved in Actual certification test flights that involve manoeuvres outside the envelope and even pushing the boundaries. These flights are ONLY carried out to determine what the envelope actually is compared to the theoretical engineering limitations. This is what sets the AFM limitations for in service operation.

Once certified, unless the aircraft undergoes a major structural change which could affect the limitations set out in the AFM, there is not requirement to revisit those tests.

Most major heavy maintenance will require system validation in flight for certain systems. None of those tests tequire the pilot to operate the aircraft to the extremes of its performance limitations. They are the regular systems checks that would be carried out at some point by a pilot during operation. For example, Alternate power and emergency power checks (ADG / RAT) Possibly a Manual gear extension (no longer requires a verification flight if tested on the ground). Generally any system that cannot be satisfactorily tested in the hangar on the ground. These flights do NOT fall into the regime of "Test Flight" even if that is what you call them. These are verification flights.

If the aircraft was significantly changed to a point where the C of G would be affected or flight control systems altered or a different engine fitted that the original TC specified. then a Certification test flight would be required and would require a trained Test Pilot. Unless you are working in a specialized business like Field Aviation which does this sort of thing then you will rarely if ever need a "Test Pilot".

FWIW flight with the landing gear extended is a NORMAL operation. Pilots do it on EVERY flight.

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FWIW flight with the landing gear extended is a NORMAL operation. Pilots do it on EVERY flight.

Yes, indeed....during take-off and landing :biggrin1:

I think the point that was being made was that on occasion most pilots have been tasked to "bring it home" with the gear down. That type of flight is a real PITA because of the reduced airspeed and max recommended altitude or max altitude designated by base maintenance.

Nothing like flying from Eureka to YTR, gear down, at 160 kts IAS up at 10-11K when cruising speed was close to TAS of 325 kts :glare::excl:

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pretty much all of us flew an aircraft gear down for several hundred hours. Its not like its a new thing.

Down and welded that is.

Rumour has it that some of you even flew gear down with 0338369.jpg

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