The de Havilland DH.53 "Humming Bird" – Performance Details and Pilot’s Notes

 

 

The red mark on the trim quadrant is a good compromise setting for full throttle (4,000 rpm) takeoffs and level cruising @ 3,500.

 

The best climb is full throttle @ 45-50mph (40-45 kts), for general climb and approach aim at 45mph (40 kts).

 

Initial rate of climb is under 400 fpm.

 

Typical climb rate is around 250-280 fpm

 

Maximum engine revs are 4,000 rpm, which gives around 71 mph true (59-62 Kts).

 

Normal cruise setting of 3,500 rpm, gives an indicated cruising speed of around 60 mph (53 Kts)

 

Remember that she stalls at 32 mph (28 Kts).

 

The ceiling? we've seen over 8,500 ft, maybe she could be persuaded up to 10,000, but 15,000 ft ???? (that's what the historical data tells us she'll do!).

 

On the ground, the combination of a narrow track undercarriage and a lightplane's tendency to yaw means this baby can be a handful, so avoid crosswind runways if you can.

 

The tickover on a small flat twin engine can be tricky to maintain at differing airfield altitudes and seasons, this compromise seems to work OK, the odd time it conks out it always restarts easily.

 

Note that the Air Speed Indicator is calibrated in MPH (not in Knots)

 

She will roll and loop (just about) but bear in mind she is really an "olde worlde" ultralight.

 

You can find some specimen test results, courtesy of Nick Tselepides (Jinx), in a folder called “DH53 Test Results” inside the main aircraft folder.

 

 

Tested in FS9, Golden Wings & FSX (but not tested in SP2/"Acceleration")

 

By Brian Farrington (Froggy), with Leyland Spurr and Jim Douglass (jimslost) – January 2008