NORTHSEATIGER From United Kingdom, joined Sep 2003, 432 posts, RR: 5 Posted (8 years 8 months 1 week 3 days 12 hours ago) and read 1612 times:
I have a few questions regarding Large fixed wing aircraft air tests, Iam a purley helicopter man so please bare with me if these questions appear stupid.
On the large turbine engined helicopters I work on if we change an engine say we will carry out ground runs for vibration, leaks, operation etc, then all being fine will carry out an airtest for power assurance and max Ng. What Iam wandering is do you do this on large fixed wing ? or can it be done on the ground, the same for say a Servo control we will carry out a handling check, is this the same ?.
And when a 747 for instance has a major inspection and requires flight tests are these conducted at some minor airfield or from Heathrow or Gatwick persay ?.
Troubleshooter From Germany, joined Feb 2005, 423 posts, RR: 5 Reply 1, posted (8 years 8 months 1 week 3 days 12 hours ago) and read 1603 times:
I´m doing line maintenance only, but I know test flights are a common practice after the bigger base maintenance events. If we have to replace for example, an aileron hydraulic actuator, all tests can be done on ground. We check for correct installation, no leaks and aileron deflection according AMM. Afterwards the aircraft is released to service again. Same applies for an engine change. All necessary tests are done in the run up hangar. There is no test flight required. Some critical tasks may only ask for a duplicate inspection.
Quoting NORTHSEATIGER (Thread starter): And when a 747 for instance has a major inspection and requires flight tests are these conducted at some minor airfield or from Heathrow or Gatwick persay ?.
I saw a video about testing the Airbus A340-600. They used special areas for their test flights. Preferrable with good weather conditions and low population on the ground. And if the big check is done at LHR, the aircraft has to take-off and land there again, of course.
AvionicMech From United Kingdom, joined Jan 2005, 315 posts, RR: 3 Reply 2, posted (8 years 8 months 1 week 3 days 5 hours ago) and read 1566 times:
As Troubleshooter says almost everything can be checked on the ground by either using on-board test equipment or sometimes external test equipment. If an engine has been changed then we will obviously carry out power assurance checks, I think for the RB211 this can be carried at a few different power settings but they are fairly near to max takeoff power.
If for example the aircraft has components in the Autoland system replaced then an Autoland check has to be carried but this is all done with on-board test equipment. It is very rare for anything to need a flight test to be checked, the only time I have seen it is on the 737, where the flight crew have been asked to do a manual deployment of the landing gear for maintenance but I think this is part of the maintenance schedule for the aircraft. The only exception is after maintenance if the aircraft is going to fly an ETOPS sector, it will then require an ETOPS verification flight.
N766UA From United States of America, joined Jul 1999, 8035 posts, RR: 25 Reply 3, posted (8 years 8 months 1 week 2 days 22 hours ago) and read 1540 times:
Any tests would be performed at the maintenance base. Major airline's maintenance bases are usually at their hubs or other large outstations. Whenever the ERJs or 737s are worked on here at CLE they're always out on the runway at 4AM doing engine run-ups and whatnot.
Lowrider From United States of America, joined Jun 2004, 3220 posts, RR: 10 Reply 5, posted (8 years 8 months 1 week 1 day 19 hours ago) and read 1482 times:
Test flights may be necessary to return an aircraft to CAT II/III status. They may also be necessary for certain autopilot functions. I know we regularly do test flights to check for proper ADG deployment and function. Certain repairs and modifications may also require flights. There is a list somewhere, but its whereabouts escape me at this moment. Test flights can depart from most any airport, but the actual tests are usually conducted over an unpopulated area or body of water.
AvionicMech From United Kingdom, joined Jan 2005, 315 posts, RR: 3 Reply 6, posted (8 years 8 months 1 week 6 hours ago) and read 1429 times:
I know that test flights that are carried out here in the UK are usually flown out to over the 'Wash' and the North Sea. This way the aircraft is away from any congested airspace so can fly around pretty much as the crew desire.
Lowrider, I know that on the aircraft that I have worked on everything in the autopilot system can be checked on the ground using on-board test equipment. What aircraft require flight tests to test the autopilot? I am not doubting you if it sounds like that, I am merely curious.
Lowrider From United States of America, joined Jun 2004, 3220 posts, RR: 10 Reply 8, posted (8 years 8 months 6 days 19 hours ago) and read 1403 times:
What aircraft require flight tests to test the autopilot? I am not doubting you if it sounds like that, I am merely curious
I did a test flight in a CRJ last year to test the autopilot in certain modes. Can't remember what work was being done, but it was a repeat write up which mx was unable to duplicate with the BITE. We went up, tested it came back, waited a few hours for the mechs to do thier thing, and tested it again. The glorious life of a reserve pilot.