Hi all,
For what it's worth, this is the procedure I follow when, as an Inspector of Homebuilt aircraft (Ireland), I am about to sign off a new aircraft for it's first flight.... I meet the builder(s) for a pre-inspection briefing so that we are all on the same sheet before we start. This is critical, as we usually make telephone contact the night before to make sure that all relevant tools, papers and equipment will be on hand and we watch the weather forecast, as expecting to fly is part of the deal.
I review all the build documents with the builder, ie, logs of all the work done, be it photographs, written notes and so on. I would have signed off critical sections such as main spars, fabric covering, wooden structure, engine mounting and so on, for being in line with the plans and also to make sure that any factory modifications or service bulletins have been accomplished. We carry out a weight and balance, if it has not already been done soon. I do a symmetry check, to make sure the aircraft is "square". We do a compass swing, if it has to have one done and write up the compass card. We do a pitot-static leak check, if it has not already been done. I check that the aircraft is legally registered and the letters and numbers applied correctly. We have to have a fireproof registration plate fixed to the cockpit or the extreme tail. We also check all of the required placards. I carry out a final inspection with all access panels and cowlings off, as if I'd never seen the aircraft before, without the builder following me around. If there is a seperate test pilot, he comes with me and we go over the aircraft thoroughly, so that he is left in no doubt as to the location of flight controls, BRS handles, how to open and close the canopy, where the canopy breaker/harness cutter is located, fuel shut-off is located and so on. He gets in and adjusts the harness to suit himself. I then get a third party to do a complete, independent loose article check before the panels and covers go back on. This is a critical step and must not be missed. We have always found unexpected objects in various cavities and I usually get someone to vacuum out the cockpit well before first flight ......we pause and have a break and finally sign off the paperwork. We close up all the panels and hatches and I brief the pilot on what I expect him to do; the engine will have had some ground running hours done by this stage and will be fit for flight. A fuel flow, fuel selection and fuel shut-off test will already have been carried out.
I brief the pilot of taxying trials, which consist of straight ahead brake testing and to carry out figures of eight, which is the best way to check steering and side loads on the gear, so I get him to do a few eights to left and right and to prove that the brakes work, the park brake works, the tailwheel lock/unlock works and that the brakes will hold the aircraft under power. What we do not do is fast power runs down the runway or hops, especially with panels missing or cowlings not fitted; the aircraft is not to do power runs without it being fully fit for flight and that includes full dress at all times. This part is to prove that the aircraft can be handled safely on the ground and responds to engine and braking control. If there are any final adjustments, now is the time.
If the pilot is happy (and insured!), then he or she can conduct a first run down the runway without lifting off. We have already appointed one person as Safety so he mans a radio and has a crash car ready with fire extinguishers,crash axe and lifting gear. We also have the phone numbers of the local doctor and the numbers for emergency services posted up. Once comms are tested, it's up to the pilot.
I have done two first flights as pilot, apart from about twelve first flights as Inspector and we stuck to the procedure and it worked very well. Every event is different but the end result is usually a delighted builder and the pop of a champagne bottle! In my case as first flight pilot, I did a preliminary run up to about 40 knots to get the feel of the aircraft before I committed to the actual first flight.
When I brief the pilot for the first flight, what we plan for is for a short initial flight, just to establish handling characteristics and general behaviour, so the pilot takes off and does an extended circuit. In both of my cases, I climbed up and did a quick pre-stall to establish the buffet speed and then used this to work out the approach speed of at least 1.25 Vs, so if the aircraft has a true stall speed of say, 40 knots, then I want 50 knots as my indicated airspeed for final approach. I then landed after about 15 minutes flight time. What we then do is get the cowlings off and inspect the engine compartment closely, to look for leaks and anything else. We also have a look around the rest of the aircraft, in case anything has fallen off or been bashed by objects unseen. After that, we close the panels up again and the pilot can then go up for a second flight, to take a bit longer to explore more of the flight envelope. I usually get them to turns, slow flight, fast flight and clean and dirty stalls and to monitor the engine Ts and Ps and record how subsystems such as GPS, radio, transponder and so on, behave. Under our rules, the initial test flight must only be conducted by a solo pilot. If the aircraft is two-seater, we usually do a few test flight first and then get the builder up for his or her first go.
We always define roles for each person present and this always works well, as it gives a great team feeling and the builder does not feel isolated or overburdened. It also gives the all-important independent eye on proceedings, as one can become blinded to small things too close to the project. in some cases, we do the test flights without family present, as this is sometimes too much for the builder to deal with, so we have had the actual, genuine first flight and then a "family" first flight the next day.
So, this might seem a bit overinvolved but it does work and we can usually do the whole thing in a few hours, with the emphasis on safety and in most cases, the first flight has gone off without a hitch and generates huge grins.


regards
Mick

Excellent write up.

Thanks.

Petter

Thanks.

I do a symmetry check, to make sure the aircraft is "square".

What exactly do you check in symmetry ?

Not exactly sure what he means, but I do one on all types that I've flown.

Approaching the aircraft, does it look right from a small distance? Anything obviously wrong like one wing lower than the other or some other thing. A low pressure tyre would cause one wing low...

I think Antoni is right, you just look at the plane from front and rear and your eye will tell you.

I take a long measuring tape or even a long piece of string and measure from the front left of the firewall to the left wingtip, starting at a top rivet or screw or staple. I then repeat the process on the right side. They should be as near to equal as possible. I then measure from the left rear of the left wing to the last bulkhead/frame of the hull and duplicate the process on the right. This immediately tells you if the wings are correctly perpendicular to the hull. You can also measure for the horizontal stabilizer's relationship to the hull and to the vertical fin. You will find symmetry and rigging drawings in most production aircrafts' manuals and some homebuilts give a pictorial description whilst others simply tell you the dimensions. It really doesn't take long to do. I flew an aircraft that was out of true and it was unpleasant, to say the least, as it required a constant aileron input just to keep it upright.  

In some cases, if a wing is out of true, it can be shimmed at the wing root to get it back in line and most aircraft have some allowance for this. In fact, a lot of commercially built aircraft have allowances for being bent or twisted. I know of a Gazelle helicopter that had been heavily landed and was out of true as a result. The manufacturer was consulted and said that as long as it wasn't cracked at the production joints, it could continue in service with an extra airframe inspection included in the maintenance schedule.

Quoted from Mick

I take a long measuring tape or even a long piece of string and measure from the front left of the firewall to the left wingtip, starting at a top rivet or screw or staple. I then repeat the process on the right side. They should be as near to equal as possible. I then measure from the left rear of the left wing to the last bulkhead/frame of the hull and duplicate the process on the right. This immediately tells you if the wings are correctly perpendicular to the hull. You can also measure for the horizontal stabilizer's relationship to the hull and to the vertical fin. You will find symmetry and rigging drawings in most production aircrafts' manuals and some homebuilts give a pictorial description whilst others simply tell you the dimensions. It really doesn't take long to do. I flew an aircraft that was out of true and it was unpleasant, to say the least, as it required a constant aileron input just to keep it upright.  

Thank you.

So, just to add to Mick's post; here's a true story (I know because I was the idiot!). When I first bought my Taylorcraft some 25 years ago, I'd taken the wings off and I'd sent the struts off for paint. The washout is set by a threaded insert on the outer end of the drag struts through which the attach bolt passes once the washout is set. I had labelled each strut and attached the labels with locking wire.... you guessed it, the painter removed them!

When I got my beautifully painted struts back I was left with a 50/50 chance of getting it right. The old bird was a battle scarred warrior with thousands of hours of flight training time before even coming to the UK so the wings weren't even a pair. Set up wasn't standard and now I hadn't a clue. So this Summer evening my licensed engineer pal and I assembled the wings and bolted everything up. Light was fading and beer beckoned! He uttered the authoritative words "It's ok! Lets go to the pub".

The following afternoon the weather was perfect and I had the afternoon off so I decided to make the test flight. I did the usual walk round and a careful check of all the bolts as I'd done a lot of work besides the painting work. Now bear in mind I was new to the aircraft and a lot less experienced than I am now.

She fired up beautifully and after the usual last minute checks I opened up, the tail came up and we started to climb. I noticed a little left wing drop and compensated but as I climbed and gained speed the left roll increased. By the time I was levelling out and accelerating I found I had full right deflection and she was rolling hard to the left. A quick stab of right rudder brought her wings level again and I was able to centre the controls before the whole nightmare started again.

I found that I had to slow down to around 55mph to slow the roll rate and so I flew a BIG circle, full deflection, stab rudder, centre the controls and repeat! I genuinely thought I was going to die! I finally got lined up and included part of the orbit as a curved final and touched down like a feather.

One look from behind the aircraft showed the problem as clear as day! I fetched a couple of spanners (sorry, wrenches) and swapped the drag struts over there and then. Fired up and took off immediately (get back on the horse!) and she flew beautifully. I learned a lot that day!