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Old 25th Feb 2018, 02:48
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Centaurus
 
Join Date: Jun 2000
Location: Australia
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I recall from the mid 1950's at RAAF Base Townsville, a USAF RB66 "Destroyer" taking off on Runway 01 which was then about 8000 ft in length and at sea level. . In those days several RAAF airfields had Distance to Go marker boards on the flight strips. I believe that was because some military aircraft used Refusal Speeds as a rough check of take off performance. It not at a certain speed by a certain distance down the runway the pilot rejected the take off.

On this occasion the B66 was a long way down the runway in its take off roll when the pilot aborted using the braking parachute as well as brakes.
It taxied back and 20 minutes later tried another take off and this time it kept going.

I suspected the pilot wanted to get home to Guam for a date

Since then, I often wondered how many military aircraft of that era aborted their take off run unnecessarily; especially as marker boards v airspeed as means of judging acceleration, was only an approximation. Some years later the RAAF dumped the idea and marker boards disappeared from military airfields.

Again, in those days, there was no such thing as take off performance charts included in RAF/RAAF Pilot's notes for type. You simply opened the throttles and went. If the runway was short you pulled back the stick when there was no runway left and hoped for the best. Believe me, I am serious! The Lincoln Pilots Notes published a recommended lift off speed and a Take-Off Safety Speed (asymmetric).
For example the Avro Lincoln PN stated in part:
At 65,000 lbs ease (rotation hadn't been invented then) the aircraft off the ground at between 100-105 knots.
75,000 lbs ditto 105-110 knots
82,000 lbs ditto 110-115 knots.
There was nothing about how much runway you needed for take off and landing at various density altitudes.

For example. The length of Momote airstrip on Manus Island,north of New Guinea, was 5200 ft. There was no over-run except to ditch into the sea. It became a case of sticking up one's wetted finger to judge the w/v and go with full power +18 lbs/sq inch boost (manifold pressure) through the throttle gate. The plan was to lift off the ground before running into the shark infested water at the end of the runway. It was safer to keep on going with an engine failure or burst tyre because an abort would be fatal.

I well recall on one take off at Momote, nil wind, the rear gunner who (naturally) faced the rear seated between his two 0.5 calibre machine guns, could see the runway going away from him, remarking upon the four trails of propeller slipstream ruffling the surface of the sea as we built up airspeed at 100 feet towards asymmetric safety speed of 135 knots. Ops normal for that era, with take off performance considerations non-existent since there were no published charts. Things were so simple, then.

Last edited by Centaurus; 25th Feb 2018 at 03:03.
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