4-5. General56
4-6. Gear Retraction56
4-7. Climbs and Descent57
4-8. Airspeed In-Flight Accuracy Check58
CHAPTER 5. EXPANDING THE ENVELOPE61
Section 1. General61
5-1. Objective61
Section 2. Hours 11 through 2061
5-2. Objective61
5-3. Stalls63
Section 3. Hours 21 through 35: Stability and Control Checks66
5-4. Objective66
5-5. General66
5-6. Definitions67
Section 4. A Word or Two about Flutter70
5-7. Objective70
5-8. Description71
Section 5. Spins72
5-9. Objective72
5-10. Caution73
5-11. Planning the Flight73
Section 6. Accelerated Stalls74
5-12. Objective74
CHAPTER 6. PUTTING IT ALL TOGETHER: 36 HOURS TO —————?77
Section 1. Maximum Gross Weight Tests77
6-1. Objective77
Section 2. Service Ceiling Tests78
6-2. Objective78
Section 3. Navigation, Fuel Consumption, and Night Flying79
6-3. Objectives80
CHAPTER 7. THOUGHTS ON TESTING CANARD TYPE AMATEUR-BUILT AIRCRAFT83
Section 1. Canards83
7-1. Objective83
Section 2. Flight Test Considerations84
7-2. General84
CHAPTER 8. ULTRALIGHT AIRFRAME INSPECTION87
Section 1. Differences87
8-1. Objectives87
8-2. Definition87
Section 2. The Test Pilot88
8-3. General88
Section 3. Pre-Flight Airframe Inspection89
8-4. General89
8-5. Checklist89
CHAPTER 9. ULTRALIGHT ENGINE/FUEL SYSTEM INSPECTION93
Section 1. Engine Inspection93
9-1. Objective93
Section 2. Fuel Systems95
9-2. General95
CHAPTER 10. ULTRALIGHT TEST FLYING RECOMMENDATIONS97
Section 1. Three Recommendations97
10-1. Objective97
10-2. Recommendations97
Section 2. Airport Selection98
10-3. Objective98
Section 3. Taxiing98
10-4. General98
Section 4. First Flight Differences98
10-5. Use of Power98
10-6. Control Feel99
10-7. Stalls99
10-8. Steep Turns99
Section 5. Emergency Procedures99
10-9. Engine Failures99
10-10. Loss of Control99
10-11. Catastrophic Failure100
APPENDIX 1. SAMPLE CHECKLIST FOR A CONDITION INSPECTION (9 pages)1
APPENDIX 2. SOURCES FOR ACCIDENT/INCIDENT INFORMATION (1 page)1
APPENDIX 3. ADDITIONAL REFERENCES ON FLIGHT TESTING (4 pages)1
APPENDIX 4. ADMINISTRATIVE INFORMATION (2 pages)1
LIST OF FIGURES
Figure 1. Runway Length Chart5
Figure 2. Empty weight CG20
Figure 3. Takeoff CG21
Figure 4. Additional Equipment Added22
Figure 5. 100 HP Fuel Flow Rate Chart34
Figure 6 Propeller Tracking36
Figure 7. Climb Airspeed and Altitude Graph64
Figure 8. Best Rate of Climb Speed Graph65
Figure 9. Static Stability67
Figure 10. Time68
Par 1-1 Page 1 CHAPTER 1. PREPARATION “The Laws of Aerodynamics are unforgiving and the ground is hard.” Michael Collins (1987)
SECTION 1. HOMEWORK “If you have no plan—you have no goal.” Harold Little, Aircraft Manufacturer (1994)
1-1. OBJECTIVE. A planned approach to flight testing.
a. Develop a Flight-Test Plan. Your most important task is to develop a comprehensive flight-test plan. You should tailor this plan to define the aircraft’s specific level of performance, so it’s important that the entire flight-test plan be developed and completed before the aircraft’s first flight.
NOTE: As part of the comprehensive flight-test plan, the test pilot should read and comprehend this entire AC before proceeding in accomplishing any suggested task.
b. Objective of a Flight-Test Plan. The objective of a flight-test plan is to determine the aircraft’s controllability throughout all the maneuvers and to detect any hazardous operating characteristics or design features. You should use this data to develop a flight manual that specifies the aircraft’s performance and defines its operating envelope. Additionally, the plan should reference the use of checklists to assure that all relevant steps and elements are covered.
c. Time Required for Flight Testing Amateur-Built Aircraft. Your original issued airworthiness certificates should be limited to operation within an assigned flight-test area for a
Par 1-1 Page 2 minimum of 25 hours when a type certificated (TC) engine/propeller combination is installed. A minimum of 40 hours is required when a non TC’d engine, propeller, or engine/propeller combination is installed. Furthermore, if the TC’d engine, propeller, or engine/propeller combination installed has been altered in a way that differs from an approved type design in a Type Certificate Data Sheet (TCDS), a minimum of 40 hours shall be required.
d. Time Required for Flight Testing Experimental Light Sport Aircraft (ELSA). If you own an ELSA experimental aircraft under Title 14 of the Code of Federal Regulations (14 CFR) part 21, § 21.191(i)(2), and it has not been modified, conduct a test flight as per their operations manual in an assigned flight-test area for a minimum of 5 hours. This applies for all classes of light sport aircraft (LSA) to determine aircraft controllability throughout its design limits.
e. Best Practices for Flight Testing After Modifying an Experimental Amateur-Built Aircraft. Before considering any modification to an aircraft previously issued an experimental certificate for the purpose of operating as an amateur-built (E-AB) aircraft, there are two things you need to consider. First is the level of modification; the other is the corresponding flight testing required for the modification. When considering the level of modification, you should first check the E-AB operating limitations. They will detail what, if any, reporting requirements there are for a given modification. This is especially important when the E-AB modification approaches the same level of a major change to TC aircraft as defined in part 21, § 21.93. Usually the owner of the E-AB aircraft is required by the aircraft operating limitations to notify the geographical responsible Flight Standards District Office (FSDO) following a “major change” as defined by § 21.93. This regulation states that a “major change” is any that affects the “weight, balance, structural strength, reliability, operational characteristics, or other characteristics affecting the airworthiness of the product. The corresponding flight testing for a major change will require at least 5 hours minimum of supplemental Phase I flight testing be completed to comply with 14 CFR part 91, § 91.319(b). The aircraft owner must obtain concurrence from the FSDO as to the suitability of the proposed test area.
(1) Flight testing in some form is advisable following any modification to the aircraft. Not only will a structured series of test flights reveal any malfunctions or unintended consequences associated with a modification, but it will also allow the pilot to become familiar with the operation of the aircraft after a given change before returning to “operational” flying.
For example, flight testing a new instrument will verify its proper operation and ensure the pilot understands how to use it. This is important to accomplish before operating the aircraft in a situation where the proper operation of the instrument may affect the safe outcome of the flight.
(2) This sort of flight testing is at the sole discretion of the owner or pilot, so it may or may not be as formal as Phase I. In general, however, the owner or pilot should conduct it in uncongested airspace local to an airport, to keep distractions at a minimum. Passengers flying for the sole purpose of pleasure should be avoided, however, because this is not Phase I testing, a passenger may be carried to monitor aircraft systems or perform other functions relevant to the purpose of the flight, if appropriate. As with any test flight, there should a clear plan with clear objectives.
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(3) It is important to note that, while some modifications are neither mandatory nor necessary to report to the FSDO, you should document all changes appropriately. The aircraft records should be updated with the date the work was completed, the hours in service of the components affected, and the total hours on the aircraft noted in the logbook along with the changes performed and the equipment added or removed. The weight and balance data and the equipment list should also be updated. Note the areas that affect operational differences in the pilot’s operating handbook (POH). In situations where the changes affect installed or needed placards and decals, they should be in place before flying with the new configuration.
(4) If the major change includes installing a different type of engine (reciprocating to turbine) or a change of a fixed-pitch from or to a controllable propeller, the aircraft owner must fill out a revised FAA Form 8130-6 to update the aircraft’s file in the FAA Aircraft Registration Branch (AFS-750). You must conduct all operations under day visual flight rules (VFR) in a sparsely populated area. The aircraft must remain in flight test for a minimum of 5 hours.
(5) At the completion of flight testing, the results should be posted in the aircraft log.
Changes should be incorporated into the POH and other affected records. The statement should, at a minimum, state the scope of the changes, the tests performed along with the results. The total hours as of that date on the aircraft should be included, and the aircraft be declared to be in a condition for safe operation.
f. Modifying ELSAs. All alterations, modifications, and additions or deletions to your ELSA must be approved in writing by the LSA kit manufacturer and recorded in the aircraft records before the original certification in experimental purpose for operation of LSA under § 21.191(i)(2).
(1) Additionally for a major change to your ELSA (such as an alteration, modification, addition, or deletion), the FAA has the authority under part 91 § 91.319(i) to modify your experimental LSA operating limitations with special restrictions for flight testing due to the aircraft modification.
(2) Following any major change, your ELSA must be assigned to a flight-test area for an appropriate time to conduct a flight test and evaluate that your aircraft is in a condition for safe operation. The guidance baseline for this testing is 5 hours of flight time within the flight-test area. The FAA may prescribe any additional limitations and/or flight time within the flight-test area deemed necessary in the interest of safety.
Par 1-2 Page 4 SECTION 2. AIRPORT SELECTION “An airport should be chosen with the same care and consideration as getting a second doctor’s opinion.” Fred Wimberly, EAA Flight Test Advisor (1994)
1-2. OBJECTIVE. To select an airport to test fly the aircraft.
a. Runway Alignment. The airport should have one runway aligned into the prevailing wind with no obstructions on the approach or departure end. Hard surface runways should be in good repair and well maintained to avoid foreign object damage (FOD) to the propeller and landing gear. Grass fields should be level with good drainage. Avoid airports in densely populated or developed areas and those with high rates of air traffic. The runway should have the proper markings with a windsock or other wind direction indicator nearby.
b. Ideal Runway. The ideal runway at sea-level elevation should be at least 4,000 feet long and 100 feet wide. For each 1,000-foot increase in field elevation, add 500 feet to the runway length. If testing a high-performance aircraft, the airport’s runway at sea level should be more than 6,000 feet long and 150 feet wide for a wider margin of safety. You should factor other considerations, such as power-to-weight ratio, wing design, and density altitude, into the equation for picking the best runway for the initial flight testing. You can also use the chart in Figure 1.
Par 1-2 Page 5 FIGURE 1. RUNWAY LENGTH CHART
Takeoff Distance in feet A - Distance to takeoff at minimum smooth lift-off speed, fly for 5 seconds at that speed without climbing, land, and stop straight ahead.
B - Distance to reach minimum smooth lift-off speed.
C - Distance covered in 5 seconds of flight at minimum smooth lift-off speed.
D - Distance to stop from minimum smooth lift-off speed (includes air and ground distance).
E - Distance to takeoff at slow approach speed and climb thereafter at an angle of 1 in 20 to 50 ft. altitude, this distance will allow most airplanes to accelerate to normal climb speed before crossing end of runway.
c. Emergency Fields. Identify emergency landing fields located within gliding distance from anywhere in the airport pattern altitude. Since engine failures are second only to pilot error as the major cause of amateur-built aircraft accidents, preparations for this type of emergency should be a mandatory part of the flight-test plan.
d. Communications. You should perform flight tests from an airport with an active Unicom or tower, even if the aircraft either doesn’t have an electrical system or doesn’t have a radio. Even at an uncontrolled field, you should improvise a communications base. For both situations, the FAA recommends a handheld radio with aviation frequencies and a headset with a microphone and a push-to-talk switch. Good radio communications improves the overall level of safety and reduces cockpit workload.
e. Physical Space. The FAA recommends you also consider the availability of hangar space and ramp areas. These facilities will provide protection from inclement weather and vandalism while the aircraft is being tested, maintained, and inspected.
f. Safety. The airport should have a telephone and firefighting equipment complying with relevant municipal codes.
g. Local Management. Explain the flight-test program and emergency plans to the airport manager or owner who may help you obtain temporary hangar space, provide ground/air communications, and supply emergency equipment for use during the flight test.
Par 1-3 Page 6 SECTION 3. EMERGENCY PLANS AND EQUIPMENT “The object of the game, gentlemen, is not to cheat death: the object is not to let him play.”
Patrick Poteen, Sgt. U.S. Army
1-3. OBJECTIVE. To develop a flight-test plan with two sets of emergency plans; one for in-flight emergencies and another for ground emergencies.
a. In-Flight Emergencies. Your in-flight emergency plan should address the following:
(1) Complete or partial engine failure, especially after takeoff.
(2) Flight control problems and severe out-of-rig conditions.
(3) Fire in the engine compartment or cockpit.
b. Ground Emergencies. The ground emergency plan should train the ground crew and/or airport fire department crash crew on:
(1) The airplane canopy or cabin door latching mechanism.
(2) The pilot’s shoulder harness/seat belt release procedure.
(3) The location and operation of the fuel shut-off valve.
(4) The master switch location and its OFF position.
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(5) The magneto switch location and its OFF position.
(6) Engine cowling removal procedures to gain access to the battery location or for firefighting.
(7) The battery location and disconnect procedures.
(8) Fire extinguisher application and use.
(9) How to secure a ballistic parachute system.
c. Ground Crew. A minimum ground crew of two experienced persons should support every test of an amateur built aircraft. Your ground crew’s function is:
(1) To ensure that the aircraft is in airworthy condition for safe operation.
(2) To provide assistance to the test pilot in an emergency.
d. The Airport.
(1) If the airport does not have a fire rescue unit, the FAA suggests the ground crew have a four-wheel-drive vehicle equipped with a portable radio, first aid kit, metal-cutting tools, and a fire extinguisher. At least one person should have completed first aid training.
(2) If the airport provides a fire rescue unit, the test pilot should ensure the rescue unit and the ground crew are trained and competent in performing ground emergency functions as identified in the flight-test plan.
(3) For a small donation, some local volunteer fire and rescue companies may provide standby crew during the initial critical portions of the flight-test phase.
e. Hospital Location. The ground crew should know the location and telephone numbers of the hospitals and fire rescue squads in the vicinity of the airport and the flight-test area. If the test pilot is allergic to specific medications, or has a rare blood type, the test pilot should carry or wear a medical alert bracelet or card to alert medical personnel of the condition.
f. Fire Extinguisher. Fire extinguishers should be available to the ground crew, and a fire extinguisher should be securely mounted in the cockpit within easy reach of the test pilot. A fire axe, or other tool capable of cutting through the canopy, also should be in the cockpit.
g. Fire Protection. There is always danger of a flash fire during test flights. To prevent burns, the pilot should wear an aviation/motorcycle helmet, NOMEX coveralls/gloves, and smoke goggles. If NOMEX clothing is not available, cotton or wool clothing will offer some protection from heat and flames. Pilots should never wear nylon or polyester clothing because synthetic materials melt when exposed to heat and will stick to the skin.
h. Pilot Protection. A modern aviation/motorcycle helmet, a properly installed shoulder harness, a well-designed seat, a clean cockpit design free of protruding components/sharp edges,
Par 1-3 Page 8 NOMEX clothing, smoke goggles, and a memorized emergency plan ensure safety during flight testing.
i. Parachute. The decision to wear a parachute depends on the type of aircraft you are testing. Some aircraft have forward hinged canopies without quick release pins, or have pusher propellers, increasing the chance of injury to the pilot while exiting the aircraft. Other aircraft designs may pose no exit problems. If the pilot decides to wear a parachute, check that a qualified parachute rigger has packed the parachute within 180 days. Ensure that the parachute has not been exposed to rain/moisture and, when worn, does not interfere with cockpit management. The test pilot should be thoroughly trained on how to exit the aircraft and deploy the parachute.
j. Ballistic Parachutes. Ballistic parachutes are the latest development in dealing with in-flight emergencies. A ballistic parachute is attached to the aircraft and when activated, lowers the whole aircraft and the pilot to the ground at the rate of descent of about 20 feet per second or about 1,200 feet per minute.
(1) Deployment Scenarios. You might deploy a ballistic parachute in case of:
(a) Structural failure.
(b) Mid-air collision.
(c) Stall/spin.
(d) Loss of control/icing.
(e) Engine failure over bad terrain.
(f) Pilot incapacitation.
(2) Installation Considerations. You should consider the following when installing a ballistic parachute:
(a) Match the parachute to the aircraft’s size, weight, and Vne speed. Check with the parachute manufacturer.
(b) How to position and mount the parachute.
(c) The parachute’s effect on the aircraft’s weight and balance before deployment and aircraft’s touchdown attitude after deployment.
(d) Compatibility of the opening loads and the aircraft’s structural design limits.
(e) The routing of the bridle and harness.
(f) The routing of the activating housing.
(g) The placement of the activating handle in the cockpit.
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(h) Incorporation of parachute deployment procedures in the in-flight emergency plan and emergency checklist.
(i) The deployment time, from activation to full parachute opening.
(3) Inspection Recommendations. If a ballistic parachute is installed, the builder should add the appropriate ballistic parachute inspection items to the aircraft’s preflight inspection checklist. The builder also should add the ballistic parachute manufacturers repack/refitting schedule and maintenance inspections to the flight manual and the conditional annual inspection checklist.
SECTION 4. TEST PILOT “We are looking for a few good Men and Women!” Marine Corps advertisement (1991)
1-4. OBJECTIVE. Select a qualified individual as the test pilot.
1-5. GENERAL. The test pilot should be competent in an aircraft of similar configuration, size, weight, and performance to the test aircraft.
1-6. TEST PILOT REQUIREMENTS.
a. Minimum Requirements. A test pilot should meet the following minimum qualifications:
(1) Physically fit: Test flying an aircraft is a stressful and strenuous task.
(2) No alcohol or drugs in the last 24 hours.
(3) Rated, current, and competent in the same category and class as the aircraft being tested.
(4) Current medical and biennial or flight review as appropriate, or a current USUA certification and flight review.
b. Suggested Test Pilot Flight Time Requirements. Each test pilot must assess if his or her level of competency is adequate, or if additional flight training is necessary. If you determine you are not qualified to flight test an unproven aircraft, you must find someone who is qualified. The following suggested number of flight hours is only an indication of pilot skill, not an indicator of pilot competence.
(1) One hundred hours solo time before flight testing a kit plane or an aircraft built from a time-proven set of plans.
(2) Two hundred hours solo time before flight testing a unique design or high-performance aircraft.
(3) A minimum of 50 recent takeoffs and landings in a tailwheel aircraft) if the test aircraft is tailwheel equipped.