Handling Impressions
My
flight in the Aero Commander was from Melbourne Airport and I flew with Airways
Surveyor Eric Sims, one of the DCA pilots who ferried the Commanders from the
States. After walking around the aeroplane and checking the various items listed
in the preflight inspection we entered the cabin with no more effort than that
required to board a modern sedan car and seated ourselves in the very comfortable
pilots' seats. The rudder pedals are fixed, but the seats are adjustable and there
is ample legroom for long legged pilots such as myself. As the control columns
are located at the sides of the cockpit with the control wheels mounted on extension
arms the cockpit floor is unobstructed and entry or exit from either pilot's seat
can be achieved quickly and without any of the usual contortions associated with
such actions.
Starting up procedure calls for first checking that the parking brake is on, this
is applied by depressing both toe brake pedals in the usual manner and then pulling
out the parking brake control on the central pedestal, the undercarriage safety
lock should be engaged and the battery and generator switches on. The Aero Commander
is equipped with electrically operated fuel valves in place of conventional fuel
cocks and the switches to operate these valves are located on the electrical panel
above the windscreen. This system requires electrical power to be available in
order to change tanks. The desirability of such a system is, I feel, open to question
although, no doubt, the possibility of a complete electrical failure in such a
well equipped aeroplane as the Aero Commander is very remote. A priming pump is
provided, but priming is unnecessary for a warm start. The electric booster pumps
should be on and with the throttle set approximately 1/8 in. open and the magneto
switches on "both" the engine is ready to be turned over on the electric
starter. As the engine fires the mixture control should be moved forward out of
idle cut off position and the throttle adjusted to idle at approximately 1000
revs. As both engines are equipped with hydraulic pumps and generators starting
order does not appear to be important.
After starting up we called the tower for taxy instructions and proceeded to taxy
out. Visibility from the cockpit of the Aero Commander whilst taxying is of the
highest standard, the wing tips are clearly visible and the aircraft rides extremely
well with a minimum of pitching movement. One's first impression is that of being
unusually close to the ground, but this is not unpleasant nor disconcerting in
any way. Eric Sims taxied out at Essendon and carried out the first takeoff, our
agreed upon plan being to fly across to Bacchus Marsh aerodrome where I would
do some upper airwork and general handling before carrying out some circuits and
landings. I subsequently found at Bacchus Marsh that while the Aero commander
is in no way difficult to taxy the technique is slightly different in that the
Aero Commander is equipped with a power operated steerable nosewheel and nosewheel
steering is activated through the toe brake pedals rather than the rudder pedals.
The first pressure on the toe brake pedal steers the nose wheel and a further
pressure applies the brake. The art is easily mastered and taxying presents no
problem. Left to its own resources the Aero Commander shows no inclination to
do anything except keep rolling straight ahead.
Arriving at the holding point we ran the engines in turn up to 1500 revs to exercise
the propellers and then to 2200 revs for a magneto check. Pre-takeoff drill calls
for mixtures rich, pitch fully fine, undercarriage lock off, fuel selector valves
on centre tank, electric booster pumps on and flaps set at the quarter extended
position.
Eric Sims takeoff from Melbourne Airport was most impressive. The fuel load
was light and only two up, but the aircraft had been ballasted up to its maximum
all up weight of 6500 lb. and performance was truly representative of full load
operation, acceleration on takeoff was rapid and the climb away steep. Rate of
climb appeared to be in the vicinity of 1200-1400 ft./min. Once clear of the Melbourne
circuit I took over control and on the short flight to Bacchus Marsh settled down
to get the feel of the Aero Commander. Visibility in flight in all important directions
is excellent and noise and vibration levels low, all three controls are effective,
positive and well harmonised, but when judged by light aircraft standards, stick
forces are a little high. Cruising at 2000 ft. using a power setting of 22 in.
x 2500 revs the Aero Commander at first indicated 148k, but this speed slowly
built up over a period of six or eight minutes and finally settled down to 155k.
Outside air temperature at the time is was plus 8 deg. C, but as position error
at this speed is -4k TAS remains approximately 155k. The Aero Commanders
mander's cruise performance improves, of course, with altitude and at 10,000 ft.
using 70% rated power the handbook quotes a cruising speed of just over 180k.
No opportunity existed on this flight to check high level cruise performance,
but the DCA-pilots who have flown the Commander state that the performance figures
in the handbook are accurate.
Arriving in the Bacchus Marsh area we climbed to 3000 ft. and after experimenting
with some turns and general handling set out to explore the stalling characteristics
of the Aero Commander. With power off and flaps up the nose has to be held quite
high in order to wash the speed back and I found that the stall occurred at an
IAS of 65k. There was some slight aerodynamic warning of the approach of the stall
and an electric stall warning device sounds off some 10k before stalling speed
is reached. With power off and undercarriage up the stall warning buzzer is a
little difficult to hear above the clamor of the undercarriage warning horn. The
stall when it occurred was quite docile and resulted in a dropped port wing, normal
recovery action resulting in full control being regained with a loss of approximately
300 ft. Aileron control remained effective down to the point of stall. With undercarriage
down, full flap and no power the stall was delayed down to 57k, the port wing
dropping a little more sharply this time and recovery taking a little longer.
Single engine performance of the Aero Commander is most impressive. Cruising at
150k at 3000 ft. I found that feathering the port engine resulted in only a slight
yaw which was easily checked with moderate pressure on the rudder, and with the
rudder trim adjusted to correct for the yaw we cruised comfortably at 120k using
only 70% power on the good engine. Control was most effective and I found that
turns into or away from the dead engine could be effected with adequate control
and no loss of height.
After unfeathering the port engine we descended to circuit height and Eric Sims
carried out the first approach and landed onto Bacchus Marsh strip to show me
how it should be done. Upon trying my own hand at some circuits and landings I
found that the Aero Commander is a very docile aircraft to handle in the circuit.
There is practically no swing on takeoff, acceleration is rapid and the nosewheel
should be lifted off the ground at 60k. A firm backward pressure on the wheel
will lift the Commander off the ground at 85k and the initial climb is made at
105k. After the undercarriage is retracted the revs are brought back to 3000 and
the flaps pulled up before a further reduction in power is made by bringing the
revs back to 2750; the climb is then continued at 130k. The initial angle of climb
is steep and I felt reluctant to pull the nose up high enough to keep the climbing
speed at the recommended figure. On the downwind leg, speed should be reduced
to 140k before the undercarriage is lowered and after it is lowered the safety
lock should be engaged. Half flap is lowered at 130k and the remainder of the
circuit is flown at 100k. Turning final, electric booster pumps should be on,
pitch fully fine and full flap lowered when ready. With speed back to 90k on final
the Aero Commander descends at a comfortable angle and as the threshold of the
runway is crossed the power is pulled off as the wheel is brought back and the
aircraft sinks gently onto the runway with little float. Once on the ground a
determined pull on the wheel is necessary to hold the nosewheel off until elevator
control is lost. Landing distance over a 50 ft. obstacle at sea level is 1500
ft. and this distance exceeds by 8 ft. the distance required on takeoff at sea
level to clear a 50 ft. obstacle.
After two or three circuits I began to feel quite at home in the Aero Commander
and thoroughly enjoyed the experience. With the exception of the location of the
flap and undercarriage indicators which are installed on the extreme right hand
side of the instrument panel and, therefore, a little difficult to see from the
left hand seat I thought that cockpit and instrument layouts were particularly
good with all important controls and instruments ready to hand and easy to locate.
One pilot operation should present no difficulty.
The time finally came to return to Melbourne Airport and upon our last takeoff
from Bacchus Marsh Eric Sims demonstrated an engine failure just after takeoff.
Decision speed is 75k and once this speed has been reached the takeoff may be
continued on one engine. Simulating an engine failure at 80k we feathered the
port engine and climbed away at an indicated airspeed of 90k-95k using full throttle
and 3000 revs on the starboard engine. Rate of climb was approximately 400 ft./min.,
a creditable performance for any light twin.
After another landing back at Melbourne Aiport I reluctantly parted company
with this very nice aeroplane. DCA will use their Aero Commanders for communications
duties and they will replace Anson aircraft now being discarded as obsolete. As
there are more than two Ansons to replace it is possible that further orders might
follow, with eventually one aircraft of this or a similar type based in each region.
The Aero Commander has much to offer as an Executive or VIP aircraft and there
is little doubt that we will see more of it in Australia in this role. Apart from
its excellent performance, ease of access to the cabin and the fact that the passengers
and crew may change seats in flight make the Aero Commander an attractive proposition
for executive use. Unfortunately, the price for such convenience is high. The
Australian agents for the Aero Commander, E. L. Heymanson & Co. Pty. Ltd.,
quote the price of the standard 560E as $78,400 flyaway Oklahoma.
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