Bits and Pieces
Flight Testing Your Home-Built - Your First Flight
By Jack Dueck, EAAHAC, EAA # 337912
“I’ve spent the last 3 or 4 or 6 or 15 years, building my own home-built aircraft, and now that I can’t think of anything else to do, or change, or add, it’s time to go flying!”
The first flight in your own home-built is probably the singular most important and momentous moment of your entire flying career. You have completed the construction of your aircraft; you have passed the inspections; you have received your flight authorization. Now it’s time for that proof of concept; that first flight! I would like to explore the many facets of ‘flight-testing your homebuilt’ in a series of columns.
There will be a large amount of internal pressure on the pilot for this first venture into unknown territory. Combined with the obvious high risk associated with a first flight, it becomes obvious that every effort be leveled at managing the risks and reducing the test flight to as safe a process as possible. Consequently, let’s consider what can be done to achieve a safe, successful and uneventful first flight:
If you, the builder, have the qualifications and experience, the first flight of your home-built can be an extension of the building process. Transport Canada requires you to be a qualified pilot, current in a similar type with a minimum of 100 hours of PIC. If you can fly in a similar aircraft with a buddy, you will gain a good deal of confidence for your first flight. If, however, you are uncomfortable in this challenge, consider asking a pilot with test flight experience to perform the first flight or the first five hours of testing your aircraft. After all, you have invested a good amount of financial and human resources to get your aircraft to this point on the ramp. Why not continue to assure the best possible outcome of your investment? You will have ample time to revel in your creation and explore the continuing expansion of your flight test envelope in the coming days.
To make sure that your aircraft is indeed ready for its first flight, get an EAA Technical Counselor or equally qualified buddy builder to go over the aircraft in minute detail to check out all those little items that you as builder may overlook. Often a second set of eyes can pick up a missed safety locking device, a loose fiber nut, etc. On our RV-9A, with complete confidence in our personal inspections, our Tech Counselor found an aileron hinge bolt un-safetied and overlooked!
With all the paperwork filed, have you thought out the simple emergency procedures? Think of Murphy’s opportunities to screw thing up for you. Your completed Pilot Operating Handbook (POH) will eventually contain a list would include:
- Engine failure during takeoff
- Engine failure immediately after takeoff
- Turn-back altitude requirements
- Engine failure during flight
- Emergency landing – no power
- Engine fire during ground start
- Engine fire in flight
- Electrical fire in flight
- Cabin fire
- Wing fire
- Electrical/Alternator failure
- Upsets. Stalls, spins
Under each heading, summarize procedures appropriate to your specific aircraft. For instance under a heading: “Engine Failure Immediately After Takeoff”
- Fly the aircraft
- Mixture – idle/cutoff
- Fuel selector – off
- Ignition switches – off
- Wing flaps – as required
- Master switch – off
- Land straight ahead (Do not attempt to turn more than 15 degrees.)
Going over each emergency procedure and listing the appropriate responses in their appropriate order will prepare you should this event occur.
Fuel and Fuel-flow:
You will have completed a ‘Fuel-flow and Unusable Fuel’ test for your aircraft. This test and it’s results will have been submitted to your inspector prior to receiving your flight authority document. So you know that under normal climb conditions, your engine will not experience fuel starvation. So now ask yourself; “Why do pilots on their first flight run out of fuel?” Certainly, this is a completely manageable risk! When I take up a newly minted aeroplane on its first flight, I can and will ensure that I will not run out of fuel on the first flight. I will measure or add or do whatever necessary to ensure that each tank will have a minimum quantity of fuel plus a reserve of at least 30 minutes for the allotted test flight time. Carrying additional is unnecessary, and should be avoided. In case of an incident involving a fire, you don’t want full fuel tanks.
Weight and Balance:
Every homebuilt aircraft is unique and has its own C of G envelope. If your aircraft is a kit from a known manufacturer, you will have a guide as to how to load ballast if necessary. If not (and you should check), you will want to have a conventional aircraft loaded to give you a C of G location approximately 25% of the C of G range from the forward recommended C of G limit. (About ¼ of the way back from forward limit). If you do not have a recommended C of G range with fore and aft limits, chose a location approximately 22% of the Mean Aerodynamic Chord (MAC) of the aircraft, (see Figure below), which corresponds closely and slightly ahead of the aircraft’s Centre of Lift (cL).
Aircraft Takeoff Weight:
Since you will be the only occupant, with a minimum required fuel quantity, zero baggage, and no unnecessary items such as portable GPS, charts, etc., your overall aircraft weight will not be excessive. Consequently, your aircraft’s performance will be enhanced. (A good scenario for a first flight.)
Set yourself firm and conservative ‘go’ and ‘no-go’ parameters for weather conditions. For example, if your aircraft has an expected stall speed of 60 mph, your operational 90 degree cross-wind of 25% (or 15 mph) should probably be reduced to a maximum of 5 mph for your first flight. Similarly; visibility, ceiling, and weather forecast conditions, should all be conducive to a safe ‘first’ flight. Better to postpone the event then to have to explain why the ground-loop was probably predictable!
Your choice of airport for the test flights will already have been specified on your flight authority. Suffice to say that an adequate length and width of runway are important. The area should not be congested and the flight path should keep you away from ground obstacles and danger to persons.
Familiarize yourself with the terrain and ground conditions all around the airport, so that you can immediately and safely pick out a known emergency landing spot if required.
When choosing the appropriate airport, consider the support facilities and organizations available for any emergency. Notify appropriate EMS, police, and firefighters of your intended first flight. You don’t need to make an issue of it, but if emergency personnel are aware of your plans, vital moments will not be lost on getting rescue operations into gear should the need arise.
Do not invite the community of friends and relatives to the first flight. EAA has a video available of a first flight where the builder of a canard pusher invited everyone to the great event. With the mounting pressure on him as the pilot, and the gathering of persons and excitement of the occasion, the video records the takeoff run with the unlocked canopy opening, then closing, then opening again while the aircraft is careening from side to side. Then finally the canopy is torn off, flies through the pusher prop and the aircraft appears as a noble experiment ending in ignominious defeat!
Your support crew should consist of a minimum number of persons. It should include your EAA Flight Advisor, and a driver of a four-wheel emergency vehicle. This vehicle should include fire extinguishers, a fire axe and assorted tools to get into the cockpit or cabin, and first aid equipment.
Your Flight Advisor will manage the flight data and support the pilot. The pilot will fly the aircraft.
That’s it. Anyone else is superfluous, and distracting to the process. There will be ample opportunity to invite friends and family to an official first flight after the testing and pressure issues have subdued.
In our next column we will carry out our first flight test. With any luck, it will be entirely uneventful, excepting the thrill and joy of seeing our aircraft in its own element of flight!