As published in the October 2003 issue of “COPA FLIGHT”- published by Candian Owners and Pilots Association.  

Homebuilder’s Flight Test Guide: book review

 

One of the well-attended seminars at the COPA Convention in Oshawa featured test pilot Tim Leslie, of the National Research Council in Ottawa.

Coincidentally, Jerry Milek, author and retired European military/test pilot, also attended and offered his new flight test checklist guide to many of the attendees.

Many good points were introduced at the seminar related to safety and flight testing procedures. As a pilot frequently involved in evaluation and flight test programs I was curious about the presentation.

I learned a short form for remembering the airspeed conversion names.  ICE T is the acronym for Indicated, Calibrated, Equivalent and True.

However, with all due respect to Leslie who presented an excellent and well understood forum, there is a quantum difference between flight testing Canadair Challenger series aircraft and a Van’s RV-6 or for that matter any of the hundreds of homebuilt types this author has flown.

Moreover, the observations that follow also relate to Milek’s booklet - which would be very useful - to a point - to many readers who conduct flight test programs on their aircraft.    

Firstly, when a builder flies an amateurbuilt for the first time, it is not the equivalent of test flying a new prototypal aircraft (unless it is a one-off design or a proven design with a great deal of aerodynamic changes - and good luck getting the inspector to approve radical modifications).

Incidentally, pilot/builders are reminded they must comply with the CARs with respect to currency and type qualifications to conduct initial flight tests on homebuilts.

To continue with the book review, the Flight Test Checklist - Homebuilder’s Flight Test Guide (HFTG) has an excellent introduction as it covers many of the considerations and tests one should complete - but likely wouldn’t think of - many accomplished before taxiing the aircraft.

The guide is based on 10 years work by Milek and used a great deal of the information from the excellent American FAA Flight Test guide - a document I have lauded many times in my writing.

Milek has invested a lot of effort in collecting data from many sources to hone his HFTG.

Although the book (spiral bound to be easily used and flipped over in the cockpit) is purported to be a guide for amateurbuilders, the depth of the HFTG goes way beyond the scope and desirability of flight testing for the average homebuilt.

The exception might be a very advanced  and rare homebuilt that has a broad flight envelope such as the Bede 10 Jet. For that matter, I believe a number of those particular  “amateurbuilts” have been lost in flight testing.

However, for the typical homebuilt and its builder, the full flight test program is overkill.

I also have some issues with the average pilot/builder flying along in an aircraft he is not overly familiar with holding a pen in one hand while making entries in his HFTG clipped onto his knee board or balanced on his knee while maintaining an adequate lookout and control of the aircraft with his other hand. The prime importance during the initial flight testing is to maintain control of the aircraft while confirming it behaves in the same manner as all of its brethren.

The written data one might commit to the HFTG is of relatively little importance as accident investigators retrieve it from the smoldering wreckage.  Essentially, in amateurbuilding, when we have a problem with an aircraft, we fix the problem immediately and then continue the test program.

It’s different with new prototypes undergoing flight test that might need some major modifications. The Beech Starship is a good example of an aircraft that had more aerodynamic refinements required than a federal budget.

Incidentally, a trick I use for many of the flight tests I complete, especially for the somewhat more complex aircraft is to carry a tape or solid state recorder. It can be wired into the aircraft system or simply carried in a pocket with the microphone taped/clipped to the boom mike of your headset or helmet. (Carry a spare tape and let the recorder run for the duration of the flight).

Another problem I have with the HFTG is the Powerplant Test program. I am strongly opposed to the policy of running the engine at full power on the ground for up to 20 minutes.

These folks with nothing but turbine time might feel this is a good test (albeit with a huge fuel flow), however, this could be a deadly test for your piston powered engine and will definitely shorten its life as cooling in almost every installation would be inadequate.

Sorry to say this, but many of the flight checks and assessments are too difficult for the average pilot I have flown with. A test pilot must be able to fly precisely to ensure the accuracy of the data during the certification process. They have equipment on board or through telemetry that note all flight parameters to confirm data.

Pilots of homebuilts typically have not achieved this level of piloting skill and therefore would be overly challenged to meet the flight test requirements. For instance reducing airspeed one-half knot per second during stall testing - while maintaining a good lookout and full control of the aircraft in level flight - is too challenging for most pilots to accurately accomplish. Besides, this type of testing is only important to ensure an aircraft meets certification requirements.

Since amateurbuilt aircraft are not certified and do not have to meet these standards, much of the testing is inappropriate and some of it could be dangerous as it takes the pilot’s attention away from more important matters.

I can just see a pilot conducting the stall testing early in the program and being locked into the airspeed indicator and second hand of the clock while the cylinder head temperature is soaring and the engine seized during power on, landing configuration stall checks.

Another caution is necessary for the spin flight test.  Many new pilots have never done spins during their training and the flight test program for your aircraft is likely not a good time to subject yourself to a rather radical manoeuvre that may overwhelm you - after all, it killed hundreds in the first world war.

Many homebuilts wind up to very high rates of rotation during spins and can easily disorient pilots not used to the gyrations. Additionally, some homebuilts have never been spun by the kit company so if you conduct spin testing you are truly an experimental test pilot - good luck. 

Still other amateurbuilts enter flat spins and cannot recover from these spins.  Enter spins in these aircraft and you will likely pay the ultimate price.

So, is this guide of any use?  Definitely!  Many of the chapters have thought provoking ideas which have been well thought out. The HFTG has many tips that expand the checklist items and add cautions or alerts to prepare the pilot for emergencies that may not have been anticipated. Well done.

As long as pilots approach the HFTG flight test checklist cautiously, it can also be a significant educational tool and guide for expanding not only the aircraft’s envelope, but also the pilots ability to recognize and appreciate the aircraft’s handling and performance.

The 115 page book’s price with taxes and S & H is $22.44. Payment and orders can be made on the web page http://members.rogers.com/test-flight

The company address is Javifix Inc. P.O.Box 63, Post. St. A Mississauga, ON L5A 2Y9 Cheques and money orders to be made out to Jerry Milek. E-mail should be directed to javifix@rogers.com

 

Photo caption:

Flying an amateurbuilt for the first time is nowhere near the equivalent of test flying a new prototypal aircraft. COPA archive photo