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Monday 16 Nov 2009
1.4 air time
1.3 flt time

Inter-flight activities:

  1. Installed missing standby alternator control wire.
  2. Moved fuel flow transducer to be between engine-driven fuel pump and fuel injection servo.

Purpose:

  1. Standby alternator functional test.
  2. Fuel flow indication test.
  3. CHT cylinder-to-cylinder difference check.
  4. Engine restart tests.
  5. Glide performance tests.

Events:

  1. Checked standby alternator performance between 1800 and 2100 rpm.
  2. Checked fuel flow indication stability.
  3. Checked CHT values in climb and cruise.
  4. Conducted engine shutdown and restart tests.
  5. Conducted glide performance tests with prop windmilling and with prop stopped.

Results:

  1. The standby alternator maintains essential bus voltage at 12.9 volts with battery master and alternator OFF, and rpm at 1900 rpm or higher. Bus voltage starts to decrease at 1800 rpm (12.8 volts). All essential bus-powered avionics were ON for this test.
  2. Fuel flow indication is much, much more stable than before.
  3. All four CHTs are now within 30 deg F of each other the vast majority of the time.
  4. The engine restarts instantly once the mixture is moved from OFF to rich, with the throttle cracked open. The indications of engine failure at idle are very, very subtle, as the prop maintains the engine rpm at the selected value, and there is very little change in thrust. The fall in EGTs is the clearest indication of engine failure at idle.
  5. Once the mixture is pulled to OFF, it is extremely difficult to get the prop to stop turning. It persists in windmilling, even as the speed is slowed to the stall with flaps UP. The prop will eventually slow and stop, if flaps are selected to FULL, and the airspeed is held just above the stall for about two minutes. Once the prop was stopped, the airspeed could be increased to about 95 kt before the prop would start turning again.
  6. The glide performance was measured in reciprocal heading descents, with prop windmilling (mixture OFF, prop control full aft, throttle at idle) at 80, 90, 100, 110 and 120 kt.
  7. The glide performance was measured in reciprocal heading descents, with prop stopped (prop control full forward, throttle at full) at 80 kt. The glide ratio was approximately 9.4:1, based on hand-recorded data.
  8. Full glide performance results will be reported later. Update 22 Nov 2009 - The results from this flight were reported here.

New Snags:

  1. None.

Existing Snags:

  1. Max rpm still decreases late in the flight.
  2. Pitch trim speed of movement is slow during a touch and go. Need to try it with the pitch trim speed governor removed.