Operating
out of Roma in southern Queensland, on 19 March 1961 about midway
along a survey run there was a sudden explosive sound of escaping
air. Maurie Miller was the technician attending to the magnetometer
trace and Bob (“Yippee”) Rennick was the navigator. If we were
enjoying the sunrise, this rush of escaping air brought us back
to a situation which needed resolution. I realised it had to be
the pneumatic system which had blown a seal somewhere (confirmed
by the zero reading on the pneumatic gauge) and that we would
have no brakes on landing. Rather than terminate the flight, we
continued to get as many line miles as the onset of turbulence
would allow and then headed for our base, Roma. Tail wheeled aircraft
are inherently unstable directionally on the ground and Anson
aircraft were as unstable directionally on the ground as any aircraft
I have flown. I was concerned that I could easily damage the landing
gear if, without brakes, I groundlooped during the landing run.
Overflying the field, which had landing strips which crossed at
rightangles, I checked the wind socks and chose to land towards
the east, which was most into wind. I got Yippee to pump the hydraulic
flaps down fully while well back on final approach so that I could
adjust my landing approach and land perhaps a little slower than
normal. Also, rather than stop both engines together as was normal
with a centrally located fuel cut off handle, I tried to maintain
directional control until the aircraft had slowed to a reasonable
speed by shutting down one engine with magneto switches. Hopefully,
without brakes, this would delay the inevitable ground loop until
the aircraft had slowed to a speed which may not damage the landing
gear - or worse. After touchdown and approaching the intersection
of the strips the aircraft began to swing to the left. I had moved
the gang switch down (which normally keeps all four magneto switches
up in the “on” position) to allow me to operate the magneto switches
independently and, as soon as the aircraft began to swing to the
left I turned off the magneto switches of the starboard engine.
I arrested the swing to the left with the application of a small
amount of power on the left engine, and I kept the aircraft moving
to the left, clear of the strip. Coincidentally, I was pointing
across the field towards the tarmac, and I found that a small
amount of engine power kept the aircraft headed straight towards
the tarmac, the engine power being balanced with a slight breeze
from the north. Again coincidentally there was a slight surface
rise as we approached the tarmac area so I was able to get reasonably
close, with safety, to our normal parking position. Bill Mitchell
had a replacement rubber grommet, and the pneumatic system was
serviceable again very quickly.
Wal Bowles
11th February 2003
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