Post-Annual Inspection Part 2: Test Flight

Author’s Note: This is Part 2 of a 2-Part series. Click here to see Part 1.

Your mechanic should have test-run the engine(s) before signing off the airplane as airworthy, but it’s unlikely that he or she test flew the airplane. 

PROBLEM: Things might not have been thoroughly checked, or switches might simply not have been returned to what you consider to be the “normal” position. 

Defense: Budget time to complete a thorough engine check and to take a short, day, VFR test-hop before flying your airplane away from the shop. 

PREFLIGHT 

Powerplant — All engine, fuel system, and propeller operation using the Pilot’s Operating Handbook (POH) procedures; 

Controls — Operation of all systems like trim, flaps, cowl flaps, carb heat, deicing systems, and flight controls; and 

Electronics — All avionics including radios, navigation devices, autopilots (there’s likely an autopilot inspection checklist in the POH supplement, so use it), lightning detectors (look for false returns caused by uninsulated wiring), radar, etc. 

Hint: It helps to make a list before departing terra firma of things you’ll check once airborne. Then, use the list as a guide while in flight. 

FLIGHT TEST 

After a *very* thorough Before Takeoff check, take off and climb to a safe altitude. Important: Bring a safety pilot with you to look for traffic while your eyes are in the cockpit checking systems. Your altitude and distance from the field should allow you to stay clear of pattern traffic, but close enough to make it back if you lose power. Check control feel, engine operation, and the use of all systems and avionics just as you had on the ground and confirm a lack of surprises while in the air. Finish your short test flight by landing, taxiing back to the shop, and then completing another detailed inspection of the airplane. Bring any discrepancies to your mechanic’s attention right away, and get them fixed (and re-tested) before accepting the airplane. 

Notes From The Real World… 

Here are just a few things I’ve found when picking up different airplanes from different shops. The the list proves — beyond a shadow of a doubt — that, every now and then, a little paranoia is a good thing… 

  • Inaccessible manual landing gear extension handles, because of improperly installed interiors. 
  • Fuel selector handles that won’t move to the “OFF” position. 
  • Inoperative alternators. 
  • Safety wire missing on emergency exit window latches. 
  • Mounting screws missing on the underside of ailerons. 
  • Ailerons mounted so that they could not reach full deflection. 
  • Landing gear doors reversed (right door on the left wing and vice versa), preventing gear retraction. 
  • Instrument air (vacuum) regulators adjusted well out of tolerance. 
  • Flap limit switches out of position, inhibiting flap movement. 
  • Autopilot disconnect switches that weren’t hooked up. 

BOTTOM LINE:

Mechanics are people too — and are subject to the same human error as pilots. Find and depend on a reputable maintenance shop, but don’t forget it’s your skin, and your responsibility to make sure the airplane is ready to fly