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Old 20th Feb 2012, 11:52
  #49 (permalink)  
Centaurus
 
Join Date: Jun 2000
Location: Australia
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Maybe this will help Ghengis. I had lots of hours as flying instructor on Lincolns.
For take off we would open the power on all engines to zero boost (30 inches MP approx) on the brakes. If every thing looked OK on engine instruments we would release the brakes and open the throttles leading with the port outer a bit more than the others to help directional control until the rudders became effective. Then we selected plus 12 boost and check the RPM was 3000. +12 boost was about 54" MP.

If the runway was short (in those days we did not have take off charts and we hoped we would reach lift off speed by the end of the runway), we would go through a "gate" on the throttle quadrant to obtain maximum power which in the RR Merlin 102 was +18 boost or 66"MP. . At that power setting the noise of the engines in the cockpit was ear shattering and painful. It was just as bad in the Mustang which I flew.

We rarely used +18 boost as it greatly reduced the life of the engine. We wore cloth flying helmets which gave no noise protection and to minimize the possibility of damage to the hearing the technique used by some copilots was to hold one hand pressed hard over the ear nearest to the nearest engine (for the copilot that was the starboard inner known as No 3).

The captain had no choice since his left hand was on the control wheel and his right hand had all four throttle levers. As soon as possible after lift off we would pull back the throttles to +12 then at 500 feet during flap retraction we would reduce further to +9 boost and 2650 RPM. At +18 boost the glycol coolant temperatures would heat up very quickly which was another reason to reduce power from +18 as soon as possible after lift off.
Normal cruise in the Lincolns we flew (Mk 31 or Long Nose version) was +6 boost and 2400rpm.

In the circuit we used +4 boost and 2400 RPM then increase to 2650 RPM late downwind. Turning base we set zero boost - which was descent power - and all being well maintained zero boost until late final when, depending on speed, we would gradually reduce power towards minus 4 boost ensuring all throttles were fully closed during the round out. It was then you could hear the characteristic "popping and crackling" noise of the Merlin at idle power. If on three engines downwind with one prop feathered (happened a lot in the tropics) then power was set at +7 boost and 2650 RPM which held the speed nicely.

PS. The noise of the four Merlins in the Lincoln caused a problem one night at Townsville. There was a zoo close to base leg for runway 02 and the zoo had a tall monkey cage. It was the bloody cage that was tall not the monkeys
We were doing circuits with new pilots on a still dark night and I understand the monkeys had gone to sleep high on the perches of their cage. The copilot increased the RPM just prior to turning base and the harmonics caused by the increase in RPM and atmospheric conditions must have caused unusual sound waves to affect several monkeys who apparently involuntarily released their hand grips on the perch and fell to their deaths on the concrete floor.
The zoo owner protested to our CO who had little sympathy although he later suggested the zoo owner install a flashing strobe on the top of the cage. That was done eventually and we were instructed to make night circuits wider in order to avoid flying directly over the zoo monkey cage.

Last edited by Centaurus; 20th Feb 2012 at 12:10.
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