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FIRST FLIGHT HANDBOOK
Critical Information For The First Flight Of An Amateur Built Aircraft
by: Al Hodges
At the Safety Seminar held at Florida Memorial College in February 1993, Bill O'Brien was the key speaker. Bill is an unusual FAA employee, who exerts a great effort to help General Aviation and the Homebuilt phase of General Aviation. This was evident at the Safety Seminar sponsored by the Light Aircraft Flyers Association (LAFA), EAA Chapter 37, and Florida Memorial College. One key factor stressed during Bill's discussion was the importance of decreasing the number of fatalities among Homebuilt Aircraft pilots. The FAA is requesting an Accident Prevention Counselor Volunteer from each aviation organization to inform pilots of problems and remind everyone to be alert. Some background data are:
* From January 1983 to January 1989, one fatality weekly occurred in
homebuilts. A large majority occurred during the first 40 hours of the
* Investigation showed two main reasons for this high accident rate:
(1) Lack of adequate preparation, and
(2) Insufficient precautions taken by pilot before entering the cockpit.
* My 1989 research of the EZes disclosed high fatality statistics for a very
safe aircraft. Over 50% of EZ fatalities occurred during the first ten
hours of flight.
Note: This is understandable. I did not feel comfortable in the Long-EZ until I had flown for over 15 hours in this particular aircraft. After 100 hours and a trip around the U.S.A., I really liked the plane.-MAH
THE EZ IS DIFFERENT! SO IS EVERY OTHER HOMEBUILT!
Much of the following "Flight Test Procedures" is derived from the Long-EZ Owner's Manual from Burt Rutan.
Flight Test Procedures
Homebuilders are especially susceptible to the danger Burt Rutan calls 'homebuilder syndrome' and he offers suggestions to avoid problems. The rush to fly the newly completed aircraft is 'homebuilder syndrome' and a major factor in many first flight accidents. The remedy is to give the key to your plane to a close friend who really likes you and, preferably, a friend you owe money. Your friend will be the final authority to approve your first flight, but only after the aircraft and you are ready.
The 'homebuilder syndrome' danger often results from an individual spending all his time and money building his plane for several years while letting his flying proficiency lapse. The best procedure for preventing 'homebuilder syndrome' being fatal is to accept help from a pilot experienced in your homebuilt for the flight testing.
Pilot Experience / Pilot Check Out
Burt Rutan stresses that you, the pilot, should be current in more than one type of airplane. Current experience in more than one type of plane prepares a pilot/builder for the fact that his homebuilt is different. Rutan states a pilot should have a minimum of ten hours each in two types of airplanes within the last four months, and five hours within the past 30 days. Your homebuilt will be different from previous aircraft you have flown. A tail wheel, retractable gear, high stall speed, critical and sensitive controls, unusual attitude during take-off and landing, and many flying characteristics will be different from the plane you last flew.
The minimum pilot check out criteria are:
* Do not test the new aircraft in gusty winds.
* Use a runway at least 3,500 feet long, preferably over 4,000 feet.
(Note: I aborted two landing on a 5,000 feet runway the first time I
tried to land the Long-EZ! - MAH)
* Take several rides with an owner of the same or similar aircraft as you
learn the feel of the controls.
* Before take-off, note the attitude and relation of the ground and
runway to the aircraft. This will improve your judgment of slight flair
when you return from the first flight.
* Quickly recognize the aircraft's attitude during take-off, climb out,
straight and level flight, descending, and in landing configuration.
* Check and recheck your weight and balance.
* Take off with sufficient fuel for the flight, but not with full tanks.
The plane should not be near its gross weight.
* DO NOT PROCEED WITH TEST FLIGHT IF FATIGUED OR ILL.
Do ground and taxi tests to learn the feel of the aircraft under power. While doing taxi tests, be very careful not to ride the brakes or over brake causing heat build up to melt your landing struts. Feel comfortable with the aircraft before committing to that first flight. Do not retract gear on your first flight and stay in the pattern and/or over the airport. Your ground support should have a fire extinguisher and first aid kit available.
When starting your series of flight tests, always have a Flight Test Plan prepared and follow it. You must fly for 40 hours, so use these hours for carefully testing all systems and get to know your aircraft's strengths and weaknesses. Expand speed and CG envelopes very slowly. Burt recommends no more than five knots speed increase as you repeat each series of tests.
(End Rutan Handbook Data)
Your Owner's Manual should have a detailed series of tests for your aircraft. Bill O'Brien, FAA author, is updating FAA Advisory Circular, Number AC-90-89, due in late 1994 or early 1995. Each builder should order the updated version before flight testing.
AMATEUR-BUILT AIRCRAFT FLIGHT TESTING HANDBOOK
Superintendent of Documents, Washington, DC 20402
(The old price was $3.25.)
This "First Flight Handbook" includes a seven page guide, "Flight Testing Homebuilts," prepared by Bill O'Brien from data provided by EAA Chapter 186 President George Lutz of Springfield, VA. George Lutz is a retired Air Force Colonel, aeronautical engineer, and flight instructor. In addition, we are including a dozen FAA Accident Prevention Program pamphlets with critical information for all pilots. The handouts used during the Project Flying Start Ground School may help clarify basic aerodynamics and reasons we avoid "low and slow" flight and thunderstorms. The "First Flight Handbook" includes a list of EAA Chapter members, their construction projects, tools and equipment available, and owners of flying homebuilts. Please feel free to call upon your fellow members for help. The local EAA Tech Counselor is ready, willing, and able to assure safe construction. The new EAA Flight Advisor volunteer fills a void. Working and flying with experienced members can save lives. Let yours be one.
Safety Bulletin Board
A valuable source of safety information and service difficulties concerning many types of homebuilt aircraft is the Computer Bulletin Board maintained by the FAA. This free service is available via a modem equipped personal computer. Call:
1-800-426-3814, Modem 1200-N-8-1, 24 four hours daily. The password is SAFETY. (The modem setting probably has been up-dated.)
You can access reports for aircraft and accessories and input your experienced data to enhance safety for other homebuilders and ultralight flyers.
Aerodynamics - Real World Dangers
There are two major dangers for careless flyers, including experienced pilots.
(1) LOW AND SLOW - Turns with over 40 degrees of bank and cross-control turns.
(2) Failure to reduce airspeed below Maneuvering Speed when encountering turbulence.
In the summers of 1990 and 1992, experienced pilots crashed at Oshkosh flying low and slow.
In Ground School Aerodynamics, we learn that turns are made by banking. As the angle of bank increases, the stall speed of the aircraft also increases. The steeper the bank, the higher air speed required to maintain level flight. How much risk? Two deaths In 1990, another in 1992 during the EAA Convention at Oshkosh, and these were experienced pilots.
A cross wind component during landing is very common. Assume the active runway is RUNWAY 9R (9 RIGHT), with a 15 knot wind from 140 degrees. This is common most of the year on the east coast of Florida. More dangerous, because it is less frequent, is landing on RUNWAY 9L (9 LEFT) when the wind is from 040 degrees, which occurs after frontal passage in winter. During landing, the pilot is preoccupied with flying the plane, looking for traffic, and using the radio. As the pilot turns from base to final in these examples, the quartering tail wind increases ground speed. The pilot overshoots his turning point for final, and the aircraft drifts past runway alignment. The pilot has three choices:
(1) If slightly off, a gentle bank will align aircraft with runway.
(2) Abort the approach, go around, and try again.
(3) Let ego overpower reason. Pull the turn tight (steep bank) to align
plane with runway. Or yaw aircraft with rudder while holding a shallow
bank with opposite aileron (cross control). A cross control turn causes
the nose to drop. The pilot pulls up, speed drops, and the plane snap
rolls into a spin.
Choices one and two are successful; number three is not.
EXAMPLE: An aircraft Vso (stall speed, landing) is 67 mph. The Owner's Manual recommends air speeds of 85 mph for pattern entry and the downwind leg, 80 mph for the base leg, 75 mph for final approach, and 70 mph at touchdown. During a late turn from base to final, the wind drifts the aircraft past runway alignment. A steep 60 degree turn increases the 67 mph stall speed by 40%, or to 93 mph. Even a 40 degree bank increases stall speed to 77 mph, which is faster than final approach speed. If the pilot needs 400 feet to recover and aircraft is 400 feet above ground level, it is too late. (See pages 8 and 9 in the FAA pamphlet ON LANDINGS - PART I in this HANDBOOK.)
The second danger is structural failure of the aircraft when exceeding the designed speed and load limits. (More discussion in FAA pamphlet WEIGHT AND BALANCE). In the Aerodynamics class, we discuss Maneuvering Speed. Your Owner's Manual will display a graph of the speed limits for the aircraft for several conditions. The specific Maneuvering Speed is the maximum speed permitted during turbulence and unusual attitudes. When flying slower than this speed, a pilot cannot cause the aircraft to have structural damage while using the controls. However, pilot movement of the controls combined with weather turbulence can cause damage. Also, the speed limits are based on a brand new aircraft from the factory, with no corrosion, proper maintenance,
no substitute parts, and all the rivets, fasteners, nuts, and bolts tight. Few certified aircraft in the world still can qualify. Beware!
To avoid most turbulence (thermal turbulence), fly above 6,000 feet. Normally aspirated engines are more efficient at 7,000-8,000 feet where it is cooler and air less dense. The calm, cool air makes for pleasant flying.
COMMENT: "Structural damage" refers to failure within aircraft, such as battery clamps breaking, the floor giving under load, and cracks near connections in wings and the stabilizer.
In extreme turbulence, the aircraft may destruct. The horizontal stabilizer (typical tractor aircraft) is the weakest point and usually breaks first. The main cause of the accident will be reported as a "weather related, pilot error" crash. Stay away from thunderstorms; never pass around a thunderstorm under the anvil where the hail falls. Within a thunderstorm, up and down winds exceed 100 mph, creating a very sharp wind shear at their junction. This shear can tear a general aviation aircraft apart. When strongly reinforced Hurricane Hunter aircraft pass through the 200 mph wind shear flying out from the eye back into the storm, the aircraft must be X-Rayed after landing. A THUNDERSTORM CONTAINS MORE POWER THAN AN ATOMIC BOMB!
Squall lines precede cold fronts,
which generally move from northwest to the southeast. Often, this line of
thunderstorms will stretch across several states. Your best choice for passage
is to wait a day. If the trip is very important, land before you enter the
squall line, wait a few hours for it to pass, and when clear ahead, continue on
your trip. NEVER FLY ACROSS OR THROUGH A SQUALL LINE. (See SUCKER HOLE in this
Sucker Hole - 1992
For several years, when two or more clouds are in the sky, we have heard the Flight Service Station weather briefer say "VFR not recommended." And since this started, I have shouted that they are crying "Wolf." Any experienced pilot knows the briefer is practicing CYA, and most briefers are not pilots. So for years, we hear and ignore. Eventually, someone is going to get into trouble, maybe killed (THIS PROBABLY HAS HAPPENED), and "pilot error" will be the cause as "VFR not recommended" will be on the FSS tape.
Thursday, July 30, 1992.
My flight is from Tallahassee, FL to Oshkosh, WI, with a lunch and fuel stop at Huntingburg, Indiana. The Tallahassee Flight Service weather briefer warns of two frontal areas, one over Chattanooga, TN and one extending from Champaign, IL to Ohio across my route. "VFR not recommended" is read like a Miranda notice. Haze and two miles visibility at TLH means a special VFR departure with no problem. I climb quickly to 6,500 feet and head north. Cloud cover below soon becomes solid. At Chattanooga, I am VFR on top. Flight Watch informs of the frontal activity from Champaign, IL to Ohio with many thunder storms across my route. "VFR not recommended" results in a "Roger" acknowledgement. The Flight Watch briefer questions, "You are not going ahead, are you?" Another "Roger your information, thanks" ends the discussion. Soon the solid cover breaks, and I land at Huntingburg after four hours, thirty minutes flying from Tallahassee.
A microwaved sandwich, some fuel, and I climb to 8,500 feet, anticipating the need soon to reach 10,500 feet to pass over the Chicago TCA. From west to east, as far as I can see ahead are towering cumulonimbus (CB) formations, perhaps ten miles apart. As I approach Terre Haute, IN, I see no breaks in the line. Where a CB ends, solid clouds with light to moderate rain fill the gaps. Turning westward, I head sixty or seventy miles toward Champaign, which is reported to be the end of the easterly moving frontal activity. However, I see blue sky through a gap in the line of CBs at my altitude and I turn into my personal "sucker hole".
Light turbulence and light rain cause me to glance down to pull on carburetor heat, reduce my throttle setting, stabilize the aircraft, and slow the Long-EZ to the maneuvering speed of less than 120 knots. Then I glance at the altimeter. Instead of 8,500 feet, it indicates 13,400 feet. Up a mile in seconds! Suddenly, I see lightning off my left wing. The VSI is pegged at 2,000 feet per minute, worthless! Now I move the throttle to idle and the nose down ten degrees for an airspeed of 110 knots. The light rain becomes heavy rain, then hail. The turbulence is minor with no sensation of ascending. The altimeter slows at 15,600 feet. An ascent of a mile and a half in seconds means the updraft is over 100 mile per hour with no sensation of the vertical speed! The plane seems to be flying at 110 miles per hour straight and level. Yet, what goes up . . . !
As the plane passes from the 100+ mile per hour updraft into the natural down draft, the power of the sharp wind shear is unbelievable. The plane shudders, as if it has hit a solid wall. Negative G-forces cause everything in my shirt pocket to fly out; the ELT pops out of the clamps holding it in place. In spite of a tight seat belt, my head hits the canopy. During a flight from Bogota to Panama, I experienced CAT. Passengers and hand luggage flew through the cabin, but this hammering shock of the very sharp wind shear is far, far worse. The shuddering of the aircraft is the heaviest shock I have ever felt in a plane, so bad I do not expect to see the wings still attached. My first thought is "If this is it, so be it." Interesting, because I never use that expression. My second thought is "Thanks Burt Rutan for designing a strong aircraft, and thanks Tom Caywood and Charlie Gray for building it to specifications." The rest is anti-climatic as the down draft takes back the free ride up and I enter clear air at 9,000 feet. Using a hand held VOR, I find Mattoon, IL and stop for the night after a short flying day!
After climbing out of the Long-EZ at Mattoon, I was shocked when I saw the hail damage to the leading edges of the canard and wings and the amount of paint removed from the leading edges of the landing struts, winglets, wings, and cowling. Immediately, I walked to the rear to inspect the prop. By the time I entered the hail, I had pulled the throttle back to idle. With little or no thrust or drag, there was no wood damage. The urethane leading edge of the wooden prop eroded slightly along the outer ten inches. Close visual inspection of the EZ revealed no signs of cracks or stressed structural areas from the outside.
Early Friday, July 31, I flew out of Mattoon to Oshkosh. The damaged canard destroyed almost all the laminar flow, requiring full aft trim and some positive stick pressure to maintain straight and level flight. At Oshkosh, I talked to Burt Rutan about the hail damage.
When he heard about the trim situation, he said,
"I would not make a high speed taxi test with that canard damage."
"I just flew two hours and ten minutes getting here," I told him.
"I wouldn't taxi test it," he repeated. "Where is the plane? I'll look
I explained where I was parked, and he agreed to meet me.
Burt Rutan, flying the Catbird; Mike Melvill, builder of one of the first Long-EZes after the prototype and flying the Defiant; Bruce Tifft, maker of the propeller; and I were all parked together. Mike held an informal discussion and information exchange session for Rutan builders at the Defiant every day. After the Saturday meeting, Mike examined the aircraft and reassured me concerning structural damage. Then, he advised me to flox the holes where the hail cut through the wings into the foam, apply two layers of fiberglass, and apply micro-balloons mixed with epoxy to reform the leading edges of the canard and wings.
Mike commented to another builder, "Many people have criticized Burt Rutan for over designing his planes. But Burt never wants to have a fatality resulting from design failure even though he complied with minimum requirements."
Bruce Tifft showed everyone how great his prop resisted the forces that destroyed the leading edges of the wings and canard. He also advised me to sand lightly with a fine grit paper to restore the polish to the urethane leading edge.
The hole revealing the blue sky had ample room for the plane to fly through. The surrounding rain and clouds were very light in color, not the dark mass normally associated with cumulonimbus and severe thunderstorms. The clouds causing my IMC weather probably rose from below much faster than I could climb. No lightning was visible from outside the clouds. The thunderstorm was imbedded. Yes, I was suckered.
Once the hole closed, I should have made an immediate 180 degree turn to exit. Then I could have continued VFR westward to pass the end of the line or find an airport and land until the weather improved.
Do not let the urgency or desire to arrive at the destination interfere with flying judgment and decisions. I stress this in ground school. I received a lecture from my pilot son when I related the event.
Respect the power of nature. Do not let the attraction of a light, thin area of clouds and light rain prevent thinking rationally. There can be a "sucker hole."
Due to the tremendous sharp wind shear between the strong updraft and down draft, I do not believe an aluminum light aircraft could have withstood the abrupt, shock of the shear force encountered. The impact was incredibly severe.
Low Flying Exam
This information was originally developed by "Transport Canada" and reproduced in the National Association of Flight Instructors (NAFI) section of "Flight Training" magazine, March 1992. Then, a few more modifications were added to stress a few points.
Low flying is a killer. Since the early days of flying, every pilot is taught NEVER, NEVER fly low and slow. Before you even fly low, answer these questions!
1. How much airspeed will you lose if you abruptly enter a 45 degree bank? How much does your stall speed increase? How many Gs must you and your plane withstand?
2. What is your rate and radius of turn in a 45 degree turn?
3. How much space do you need to complete a 180 degree turn at 45 degrees of bank? (Note: Engine failure creates a desire to return to the airport, a box canyon, trees and towers, buildings, fences, etc. all limit your maneuvering space.)
4. How much more space do you need if a 20 knot wind is behind you half way around the 180 degree turn at 45 degrees of bank?
5. How far away can you see a wire? If you suddenly see a wire, what should you do?
6. If you have to jerk back on the wheel (pull up) to miss the wire, how much space will it take to change the flight path upwards?
7. If you have to pull up suddenly straight ahead, what airspeed will you have after climbing 300 feet?
8. What do you do if you run a fuel tank dry at low altitude?
9. Will your windshield withstand hitting a three pound gull? (NOTE: Or a pelican, pigeon, buzzard, hawk, or sparrow?)
10. Do you still want to fly low?
FARs - Legally, how low can you fly over: The bay or ocean? The Columbus Day Regatta or a boat race? Everglades Park? Key Largo? Pasture land? Dodge Island? The beaches? Key Biscayne? (HINT: These are located in Class B air space, national parks, towns, and uninhabited space.)
Assembled by EAA Chapter 620, Homestead, Florida (March 1993).
The following FAA reprint and pamphlets complete the "First Flight Handbook."
"Flight Testing Homebuilts," by Bill O'Brien, a reprint from "FAAviation News"
Ac No. 20-27d Certification And Operation Of Amateur-Built Aircraft
Ac No. 43-9b Maintenance Records
Ac No. 43-12a Preventive Maintenance
Ac. No. 65-23a Certification Of Repairmen (Experimental Aircraft Builders)
ACCIDENT PREVENTION PROGRAM PAMPHLETS:
Faa-P-8740-2 Density Altitude
Faa-P-8740-5 Weight And Balance
Faa-P-8740-20 Preventing Accidents During Aircraft Ground Operations
Faa-P-8740-23 Planning Your Takeoff
Faa-P-8740-29 Meet Your Aircraft
Faa-P-8740-36 Proficiency And The Private Pilot
Faa-P-8740-38 Human Behavior - The No. 1 Cause Of Accidents
Faa-P-8740-44 Impossible Turn
Faa-P-8740-48 On Landings - Part I
Faa-P-8740-49 On Landings - Part Ii
Faa-P-8740-50 On Landings - Part Iii
Faa-P-8740-53 Introduction To Pilot Judgment