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Old 2nd November 2002 | 08:53
  #15 (permalink)  
Chimbu chuckles

Grandpa Aerotart
 
Joined: Jun 2000
Posts: 4,579
Likes: 3
From: SWP
Centaurus,

I would have thought you learned in one being ex RAAF 1950s?

I last flew a Tiger a few months ago.

The method I've always used was as described above. The flooding is because that's the only way you know there is any fuel in there at all.

I swing the prop from behind. The system is not 'live' with just the rear mag switches up (on) but is so with the forward switches up as well. You can reach the front throttle and mag switches comfortably standing in front of the wing and ensure they are correct before pulling the prop through compression.

You do not need to fling it very hard at all...not much more than a flick of the wrist really is all that's needed.

The advantages of starting this way is you control all the various aspects of the start, spark, fuel and 'armstrong' starter. If the aircraft jumps the chocks (I virtually never use chocks in this method) you simply sit on the wing, and flick off the switches/close the throttle...which should only be barely cracked anyway.

And for everyone wondering why the throttle goes wide open when cranking for a flooded engine think about what the throttle actually controls...only the butterfly valve upstream of the venturi.

When you select full throttle you are merely maximising the air which can be sucked (see why it's called suck & Blow?) into the engine by the pistons....that's all...with the butterfly valve wide open (parallel with airflow) the only restriction to the amount of air that can be sucked in by the pistons is the air filter.

A flooded engine does not run because the mixure is to rich to burn...as you crank with throttle wide open (and hopefully mixture idle cutoff) you are effectively leaning the mixture, cylinder by cylinder, until you 'stumble across' the correct fuel air ratio and the engine starts....that's why it starts a few cylinders at a time as well

Chuck.
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