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Watching the Connie fire up her engines I wondered, do some radial engine planes have a two-speed starter motor to replace the ground crew "pulling the props through"?

In other words, low-speed–mags-off to test for a potential hydraulic lock.

I do realize the props could have been pulled through off-camera before being towed out for the show.

  • $\begingroup$ It appears from the other answer that hydraulic lock is only a problem after the plane has sat for a long period. Might not be necessary to pull through if the plane has been flown that day $\endgroup$
    – TomMcW
    Commented Mar 14, 2017 at 21:41
  • 1
    $\begingroup$ Btw, have you ever heard a Connie? A place in Gardner KS works on them and when they test fly it you can hear it in the next county $\endgroup$
    – TomMcW
    Commented Mar 14, 2017 at 21:43

1 Answer 1


There seems to be only one starter speed:

Proper sequence for starting radial engines...DC-6B style, with P&W R-2800's.

  • Engage start and start safety switches.
  • Rotate thru 9 blades.
  • While continuing to rotate the engine with the starter, engage primer and ignition boost switches, and at the same time, select magnetos to 'both'.
  • When engine fires, continue starting with the fuel primer engaged, releasing the start and start safety switches.
  • Slowly move mixture control to the autolean position, then release fuel prime switch.
  • Engine continues to run (hopefully).
  • Taxi in autolean, until engine run-up desired.
  • Complete run-up and propellor checks in autorich.
  • Return mixture to autolean.
  • Prior to takeoff, ensure engine mixture controls are in autorich (very important).

Have a pleasant day, thereafter (hopefully). ;-)

DC-3 about the same, except...

  • use autorich for all ground ops.
  • Engine type, P&W R-1830-92.
  • Curtis Wright engines...can't remember.

Stratocruiser, same as the DC-6B. DC-7 and Lockheed 1649, same also, as the DC-6B.

NB. Operating in autolean helps to prevent plug fouling while on the ground.

[Posted by 411A on May 18th, 2008 at pprune.org]

  • 1
    $\begingroup$ TIL auto-lean is a thing. :) $\endgroup$
    – user14897
    Commented Mar 14, 2017 at 14:11

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