AC 90-89C

Advisory circular · Amateur-Built Aircraft and Ultralight Flight Testing Handbook

Approved
February 14, 2023
Last reviewed
July 19, 2024
Cancels
AC90-89B
Family
AC 90-89 · 3 versions
Revision
C
14 CFR parts
1, 21, 23, 91, 103

Guidance, not mandatory unless a rule or AD requires it. DRS record last changed March 30, 2026.

Show pages 105–116
Page 117Open in PDF

Appendix A A-2 S = SATISFACTORY U = UNSATISFACTORY (correct all unsatisfactory items prior to flight) Builder/Inspector

S U S U

FLIGHT CONTROLS PROPERLY RIGGED/PROPER TENSION

INSPECT ALL CONTROL STOPS FOR SECURITY

TRIM CONTROL PROPERLY RIGGED

TRIM CONTROL SURFACES/HINGES/ROD END BEARINGS SERV.

FRAYED CABLES OR CRACKED/FROZEN/RATCHETING

PULLEYS

SKIN PANELS DELAMINATE/VOIDS (COIN TEST)

POPPED RIVETS/CRACKED/DEFORMED SKIN

FABRIC/RIB STITCHING/TAPE CONDITION

LUBRICATION

WING ATTACH POINTS

FLYING/LANDING WIRES/STRUTS FOR SECURITY

CORROSION

FOR ULTRALIGHT CHECK

FLIGHT CONTROL BOLTS/PINS FOR SAFETY AND

CONDITION

WING/STRUT/CABLE ATTACHMENTS AND HARDWARE FOR

SAFETY AND CONDITION

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Appendix A A-3 S = SATISFACTORY U = UNSATISFACTORY (correct all unsatisfactory items prior to flight) Builder/Inspector

S U S U

FUEL SYSTEM:

CORROSION

FUEL LINES FOR CHAFING/LEAKS/SECURITY/CONDITION

SUMP ALL FUEL TANKS FOR WATER OR DEBRIS

FUEL CAPS FOR SECURITY

FUEL PLACARD

FUEL VALVE/CROSS FEED/FOR OPERATION AND SECURITY

CLEAN FUEL FILTERS/GASCOLATOR/FLUSH SYSTEM

INSPECT FUEL TANK VENT SYSTEM

LANDING GEAR:

INSPECT STRUTS/TORQUE LINKS FOR ATTACHMENT

INSPECT STRUTS FOR PROPER EXTENSION

INSPECT FOR HYDRAULIC LEAKS

CHECK ALL BUSHINGS FOR WEAR/FREE PLAY

CHECK LUBRICATION

INSPECT WHEELS FOR ALIGNMENT

WHEEL/TIRES FOR CRACKS AND SERVICEABILITY

WHEEL BEARINGS FOR LUBRICATION

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Appendix A A-4 S = SATISFACTORY U = UNSATISFACTORY (correct all unsatisfactory items prior to flight) Builder/Inspector

S U S U

INSPECT FOR CORROSION

INSPECT NOSE GEAR FOR CRACKS AND TRAVEL

INSPECT TAIL WHEEL FOR CRACKS AND TRAVEL

PERFORM GEAR RETRACTION TEST/CHECK INDICATOR LIGHTS

EMERGENCY GEAR RETRACTION SYSTEM

CHECK TIRE PRESSURE

BRAKE LINING WITHIN LIMITS

BRAKE DISKS FOR CRACKS, WEAR, AND DEFORMITY

BRAKE HYDRAULIC LINES FOR LEAKS AND SECURITY

FUSELAGE:

REMOVE INSPECTION PLATES AND PANELS

INSPECT BULKHEADS AND STRINGERS FOR POPPED RIVETS

AND CRACKED SKIN

INSPECT FOR DELAMINATED SKIN/VOIDS (COIN TEST)

INSPECT THE SECURITY OF ALL INTERNAL LINES

INSPECT WINDOWS/CANOPY FOR CRACKS AND FIT

INSPECT DOOR OR CANOPY LATCHING MECHANISM

INSPECT FIRE WALL FOR DISTORTION AND CRACKS

INSPECT RUDDER PEDALS AND BRAKES FOR OPERATION

AND SECURITY

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Appendix A A-5 S = SATISFACTORY U = UNSATISFACTORY (correct all unsatisfactory items prior to flight) Builder/Inspector

S U S U

INSPECT BEHIND FIREWALL FOR LOOSE WIRES AND

CHAFING LINES

CHECK CONTROL STICK/YOKE FOR FREEDOM OF

MOVEMENT

CHECK FLAP CONTROL OPERATION

CHECK CABLE AND PULLEYS FOR ATTACHMENT AND

OPERATION

PERFORM FLOODLIGHT CARBON MONOXIDE TEST

ENSURE THE COCKPIT INSTRUMENTS ARE PROPERLY MARKED

INSPECT INSTRUMENTS, LINES, FOR SECURITY

CHECK/CLEAN/REPLACE INSTRUMENT FILTER

INSPECT COCKPIT FRESH AIR VENTS/HEATER VENTS FOR

OPERATION AND SECURITY

INSPECT SEATS, SEATBELTS/SHOULDER HARNESS FOR

SECURITY AND ATTACHMENT

CORROSION

CHECK BALLISTIC PARACHUTE INSTALLATION PER

MANUFACTURER

RECOMMENDATIONS

EMPENNAGE/CANARD

REMOVE INSPECTION PLATES AND FAIRINGS

INSPECT CANARD ATTACH POINTS FOR SECURITY

INSPECT VERTICAL FIN ATTACH POINTS

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Appendix A A-6 S = SATISFACTORY U = UNSATISFACTORY (correct all unsatisfactory items prior to flight) Builder/Inspector

S U S U

INSPECT ELEVATOR/STABILIZER ATTACH POINTS

INSPECT HINGES/TRIM TABS/ROD ENDS FOR ATTACHMENT

AND FREE PLAY (SLOP)

INSPECT EMPENNAGE/CANARD SKIN FOR

DAMAGE/CORROSION

INSPECT ALL CONTROL CABLES, HINGES AND PULLEYS

INSPECT ALL CONTROL STOPS FOR ULTRALIGHT:

CHECK ALL ATTACHMENT POINTS AND CONTROL FOR

SAFETY CONDITION

ENGINE:

PERFORM COMPRESSION TEST—CYLINDER #1 ___ #2 ___ #3 ___ #4 ___ #5 ___ #6 ___

CHANGE OIL AND FILTER (CHECK FOR METAL)

INSPECT IGNITION HARNESS FOR CONDITION AND

CONTINUITY

CHECK IGNITION LEAD INSULATORS (CIGARETTES) FOR

CONDITION/CRACKS

CLEAN AND GAP SPARK PLUGS

CHECK MAGNETO TIMING/POINTS/OIL SEAL/DISTRIBUTOR

INSPECT ENGINE MOUNT/BUSHINGS

INSPECT ENGINE MOUNT ATTACHMENT BOLT TORQUE

INSPECT ALTERNATOR/GENERATOR ATTACHMENT

CHECK ALTERNATOR/GENERATOR BELT CONDITION

INSPECT CYLINDERS FOR CRACKS/BROKEN FINS/EXHAUST STAINS

INSPECT ENGINE BAFFLES FOR CRACKS/CONDITION

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Appendix A A-7 S = SATISFACTORY U = UNSATISFACTORY (correct all unsatisfactory items prior to flight) Builder/Inspector

S U S U

CHECK FOR OIL LEAKS INSPECT VACUUM PUMP AND LINES

INSPECT OIL VENT LINES

INSPECT ALL CABIN HEAT/CARB HEAT/DEFROSTER DUCTS

FOR CONDITION

INSPECT CARBURETOR FOR SECURITY & CLEAN INLET SCREEN

INSPECT INTAKE HOSES/SEALS FOR SECURITY/LEAKS

INSPECT THROTTLE/MIXTURE/CARB HEAT/CONTROL FOR

PROPER TRAVEL AND SECURITY

INSPECT CARB HEAT AIR BOX FOR CRACKS/OPERATION

INSPECT CONDITION OF FLEXIBLE FUEL AND OIL LINES

INSPECT OIL COOLER FOR LEAKS AND CONDITION

CHECK EXHAUST SYSTEM FOR ATTACHMENT & CONDITION

CHECK MUFFLER/INTERNAL BAFFLE/FOR SECURITY

CHECK EXHAUST PIPES/FLANGES FOR SECURITY &

ATTACHMENT

REPACK EXHAUST GASKETS AS REQUIRED

CHECK COWLING FOR CRACKS AND SECURITY FOR ULTRALIGHT:

CHECK CARB BOOTS ON 2-CYCLE ENGINES FOR CRACKS

CHECK SAFETIES ON EXHAUST SPRINGS PERFORM 2-CYCLE COMPRESSION TEST TO CHECK SEALS

ENSURE SPARK PLUG CAPS ARE SAFETIED ON INVERTED

ENGINES

PROPELLER:

CHECK SPINNER AND BACK PLATE FOR CRACKS

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Appendix A A-8 S = SATISFACTORY U = UNSATISFACTORY (correct all unsatisfactory items prior to flight) Builder/Inspector

S U S U

INSPECT FOR CRACKS/STONE DAMAGE/NICKS

CHECK FOR DELAMINATION (WOOD/COMPOSITE BLADES)

CHECK PROP BOLTS TORQUE/SAFETY WIRE

CHECK FOR OIL LEAKS (CRANKCASE NOSE SEAL)

GREASE LEAKS (CONSTANT SPEED PROP)

CHECK PROPELLER GOVERNOR FOR LEAKS AND

OPERATION

CHECK PROP TRACK

CHECK PROP BALANCE (WOOD PROP)

ELECTRICAL

SPARE FUSES AVAILABLE

BATTERY SERVICED AND FREE FROM CORROSION

BATTERY BOX FREE FROM CORROSION

ELT BATTERY FREE FROM CORROSION AND CURRENT

BATTERY

CHECK LANDING LIGHT OPERATION

CHECK POSITION LIGHTS OPERATION

CHECK ANTI COLLISION LIGHT FOR OPERATION

INSPECT ALL ANTENNA MOUNTS AND WIRING FOR

SECURITY

CHECK ALL GROUNDING WIRES (ENGINE TO AIRFRAME, WING TO AILERON/FLAP, ETC.)

INSPECT RADIOS/LEADS/WIRES FOR ATTACHMENT &

SECURITY

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Appendix A A-9 S = SATISFACTORY U = UNSATISFACTORY (correct all unsatisfactory items prior to flight) Builder/Inspector

S U S U

INSPECT CIRCUIT BREAKERS/FUSES PANELS FOR

CONDITION

OPERATIONAL INSPECTION:

VISUAL INSPECTION OF THE ENGINE/PROPELLER

ALL INSPECTION PANELS AND FAIRINGS SECURE

PERSONNEL WITH FIRE BOTTLE STANDING BY

BRAKE SYSTEM CHECK

PROPER FUEL IN TANKS

ENGINE START PROCEDURES

OIL PRESSURE/OIL TEMPERATURE WITHIN LIMITS

VACUUM GAUGE CHECK

MAGNETO CHECK/HOT MAG CHECK

IDLE RPM/MIXTURE CHECK

STATIC RPM CHECK

ELECTRICAL SYSTEM CHECK

COOL DOWN PERIOD/ENGINE SHUT DOWN

PERFORM OIL, HYDRAULIC, AND FUEL LEAK CHECK PAPERWORK:

AIRWORTHINESS DIRECTIVES

RECORD FINDINGS AND SIGN OFF INSPECTION

MAINTENANCE IN AIRCRAFT LOGBOOKS

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Appendix B B-1 APPENDIX B. SOURCES FOR ACCIDENT/INCIDENT INFORMATION B.1 Accident/incident reports for all U.S.-registered make and model aircraft are available from the following sources:

B.1.1 Federal Aviation Administration (FAA):

https://www.faa.gov/data_research/accident_incident.

B.1.2 National Transportation Safety Board (NTSB):

https://www.ntsb.gov/investigations/AccidentReports/Pages/Reports.aspx.

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Appendix C C-1 APPENDIX C. ADDITIONAL REFERENCES ON FLIGHT TESTING The following references comprise selected additional information sources on flight testing and first flight experiences for amateur-built aircraft and ultralight vehicles. This list of informational material may help amateur builders in preparing the FLIGHT TEST PLAN for their aircraft and ultralights.

Experimental Aircraft Association (EAA) publications are available in the EAA archives, a benefit available to EAA members. Non-members can obtain copies, for a fee, by calling 1-800-564-6322.

Some of these publications are out of print but may be available on auction sites such as eBay.

C.1 Industry Publications, Amateur-Built Aircraft:

• Askue, Vaughan, Flight Testing Homebuilt Aircraft, (Ames, IA: State University Press, 1992).

• Ariosto, James, “A Two Minute Test-Hop Reveals All Wrongs,” Sport Aviation, (May 1970), pp. 29–30.

• Bingelis, Antoni, “A Report on the 1973 Oshkosh Safety and Courtesy Inspections,” Sport Aviation, (November 1973), pp. 35–37.

• ____ “After the First Test Flight,” Sport Aviation, (April 1988), pp. 27–30.

• ____ “Flight Testing Homebuilts-Stage One: Making Preparations for Flight Testing,” Sport Aviation, (January 1989), pp. 27–30.

• ____ “Flight Testing Homebuilts-Stage Two: Making the Initial Flight Test,” Sport Aviation, (February 1989), pp. 27–30.

• ____ “Flight Testing Homebuilts-Stage Three: Expanding the Flight Envelope,” Sport Aviation, (March 1989), pp. 28–31, 66.

• Donofrio, P. R., “Checkmate,” Sport Aviation, (June 1978), pp. 30–31.

• Dwiggins, Don, “Flight Testing Your Homebuilt,” Homebuilt Aircraft, (July 1985), pp. 40–43.

• ____ “Flight Testing Your Homebuilt,” Plane and Pilot, (Annual, 1974), pp. 56–61.

• Enman, Ann, “The Moment of Truth! The Test Flight,” Air Progress 1989 Guide to Sport Aircraft Kits, pp. 16–19.

• Experimental Aircraft Association, The EAA Flight Test Manual, (Oshkosh WI:

Experimental Aircraft Association, Inc., 2018).

• Experimental Aircraft Association, Pilot Reports and Flight Testing, V. 1, pg. 72 (1977). Selected first flight reports and flight testing procedures.

• Friedman, Peter, “High Tech-First flight,” Sport Pilot, (February 1989), pp. 16, 17, 72, 73.

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Appendix C C-2

• Goyar, Norman, “Free Insurance and How to Get It,” Sport Pilot, j. 5, No. 3 (1989), pp. 44–49.

• Heintz, Chris, “The First Flight of Your Aircraft,” EAA Light Plane World, (May 1986), pp. 7–9.

• ____ “Performance Testing Your Aircraft,” EAA Light Plane World, (July 1986), pp. 13–15.

• Hurt, H. H., Jr., Aerodynamics for Naval Aviators, (California: University of Southern California, 1960 [revised 1965]). NAVAIR 00-80T-80. Issued by the Office of the Chief of Naval Operations, Aviation Training Division.

• Jacquemin, G., “Flight-testing for the Amateur,” Sport Aviation, (April 1965), pg. 4.

• Kerley, Jim, “Thoughts on Test Flying,” Sport Aviation, (March 1970), pp. 34–35.

• Ladd, Robert W., “The Test Flight of Chihuahua,” Sport Aviation, (February 1968), pg. 4.

• Macq, Harvey, “Test Flight,” Sport Aviation, (March 1960), pg. 3.

• Mason, Sammy, Stalls, Spins, and Safety, (New York: Macmillan Publishing Company, 1985).

• Mitchell, C.G.B., “Design of the ‘Kittiwake’ Family of Light Aircraft,” (Part 2) Sport Aviation, (March 1969), pp. 36–37.

• Rhodes, Mike, “First Flight—Trial by Fire,” (Part 1) Sport Aviation, (August 1988), pp. 26, 27, 29.

• Smith, Hubert, Performance Flight Testing, (Blue Ridge Summit: Tab Books, Inc.

[Modern Aviation Series], 1982), pg. 131.

• Sport Aviation, “Pointers on Test Flying Complied by Chapter 32, St. Louis, MO,” Sport Aviation, (December 1960), pg. 3.

• Sport Planes, “The Sacramento Seaplanes,” Sport Planes, (Fall 1970), pp. 16–27.

• Taylor, M. B., “Testing your Homebuilt,” Sport Aviation, (January 1977), pg. 24–27.

• Tausworthe, Jim, “The Brotherhood of Flight,” Sport Aviation, (August 1969), pg. 22.

• Thorp, J. W., “Structural Flight Testing,” Sport Aviation, (November 1961), pg. 2.

• Wendt, H. O., “Designing, Building, and Flight Testing of the Wendt Wh-1 Traveler,” Sport Aviation, (March 1973), pg. 10–15.

• White, E. J., “Super Coot—The Fisherman’s Homebuilt,” Homebuilt Aircraft, (September 5, 1981), pg. 1821.

• Wood, Karl D., Technical Aerodynamics, (New York: McGraw Hill, 1947).

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Appendix C C-3 C.2 Industry Publications, Ultralights:

• Brooke, Rob, “Greatest Peril,” Ultralight Flying, (September 1993), pp. 42–43.

• Cannon, Mike, “Learning to Fly—Again,” Ultralight Flying, (June 1988), pg. 5.

• ____ “Keeping Cool in the Summer Time,” Ultralight Flying, (August 1988), pp. 16–17.

• Cartier, Kerry, “Power Failure on Take-off,” Ultralight Flying, (January 1988), pg. 25.

• Chapman, John, and Smith, Clark, “Preparing for the In-Flight Emergency,” Ultralight Flying, (March 1989), pg. 32.

• Demeter, Dennis, “Risk Management,” Ultralight Flying, (July 1993), pp. 48–49.

• ____ “Don’t Forget the Pre-flight,” Ultralight Flying, (May 1993), pp. 70–71.

• Gunnarson, Tom, “Getting into Ultralight Float Flying,” Ultralight Flying, (April 1989), pp. 27–29.

• Johnson, Don, “Getting the Most out of Flight Reviews,” Ultralight Flying, (March 1989), pp. 20–23.

• Loveman, Dave, “Problem-Solving the Cayuna 430R,” Ultralight Flying, (June 1988), pp. 24–25.

• Pagen, Dennis, “‘G’ forces and your Ultralight,” Ultralight Flying, (August 1989), pg. 37.

• ____ “Weight and Speed,” Ultralight Flying, (May 1989), pp. 20–21.

• Peghiny, Tom, “Effects of Sunlight on Polyester Sail Cloth,” Ultralight Foundation, Volume 2, Number 1, pp. 49–50, (1986).

C.3 Government Publications:

C.3.1 FAA Advisory Circulars (AC). Current editions of ACs are available at https://www.faa.gov/regulations_policies/advisory_circulars.

• AC 20-35, Tiedown Sense.

• AC 20-37, Aircraft Propeller Maintenance.

• AC 20-42, Hand Fire Extinguishers for Use in Aircraft.

• AC 20-105, Reciprocating Engine Power-Loss Accident Prevention and Trend Monitoring.

• AC 20-125, Water in Aviation Fuels.

• AC 23-8, Flight Test Guide for Certification of Part 23 Airplanes.

• AC 23-16, Powerplant Guide for Certification of Part 23 Airplanes and Airships.