Hand swinging "normal" planes
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Joined: Nov 2002
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From: Kent
Hand swinging "normal" planes
Quick question: can you hand swing/start a "normal" plane which has electrics, alternator etc? For example, as an alternative should you not be able to start with the key.
Would the process be the same as if you were hand swinging a cub, say?
Would the process be the same as if you were hand swinging a cub, say?
Joined: Aug 2000
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From: Norfolk
The short answer is yes - you can hand swing electic start aeroplanes.
The complete answer is rather more engine/type specific!
I have hand swung C152/172/182, various Pitts Specials and the largest displacement was a Beech V35B - Wonderboem back in the early '90s, hot and very tiring!.
If the engine has an impulse mag, ensure that ONLY that mag is selected when the chap in the aeroplane hears you call CONTACT. Generally this is the LEFT mag but some aeroplanes do have impulses on both sides.
On normal key-start aeroplanes (Lyc/Cont) when you turn the key to START, it mechanically grounds out the RIGHT mag therefore allowing the engine to start only on the impulse mag. When the key is released back to BOTH, the RIGHT mag is energised.
Tricycle geraed aircraft are generally easier to start as the propeller disc angle is more vertical and consequently the thrust line is closer to the ground, so no long reaches a la Tiger Moth.
Hope that this helps,
Stik
The complete answer is rather more engine/type specific!
I have hand swung C152/172/182, various Pitts Specials and the largest displacement was a Beech V35B - Wonderboem back in the early '90s, hot and very tiring!.
If the engine has an impulse mag, ensure that ONLY that mag is selected when the chap in the aeroplane hears you call CONTACT. Generally this is the LEFT mag but some aeroplanes do have impulses on both sides.
On normal key-start aeroplanes (Lyc/Cont) when you turn the key to START, it mechanically grounds out the RIGHT mag therefore allowing the engine to start only on the impulse mag. When the key is released back to BOTH, the RIGHT mag is energised.
Tricycle geraed aircraft are generally easier to start as the propeller disc angle is more vertical and consequently the thrust line is closer to the ground, so no long reaches a la Tiger Moth.
Hope that this helps,
Stik
Thread Starter
Joined: Nov 2002
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From: Kent
Thank-you!
Running on from this then, say you have flooded the engine of your C172, presumably you could then blow back with 4 pulls in the other direction, call "contact" (checking only the left mag is on), then give the prop a swing?
Running on from this then, say you have flooded the engine of your C172, presumably you could then blow back with 4 pulls in the other direction, call "contact" (checking only the left mag is on), then give the prop a swing?
Joined: Oct 1999
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From: UK
Vacuum pumps fitted to some flat engines can be damaged by turning the engine backwards.
I have hand-swung 172s and the like, but I prefer not to. Whereas something like a Tiger Moth or Chippy, with a long stroke engine, just needs gentle pull over compression for the prop to flick around, the typical flat engine (with the exception the little 65 horse Conti in a Cub which is a deligh to swing) needs a more sustained pull for longer and doesn't 'flick over'.
I have heard it's possible to hand-swing a Yak 52. Now that, having spent a long time simply pulling these engines through before flight, is something I would never do!
SSD
I have hand-swung 172s and the like, but I prefer not to. Whereas something like a Tiger Moth or Chippy, with a long stroke engine, just needs gentle pull over compression for the prop to flick around, the typical flat engine (with the exception the little 65 horse Conti in a Cub which is a deligh to swing) needs a more sustained pull for longer and doesn't 'flick over'.
I have heard it's possible to hand-swing a Yak 52. Now that, having spent a long time simply pulling these engines through before flight, is something I would never do!
SSD
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From: South Norfolk, England
KCDW,
From your posts I'm guessing that you've never swung any prop before. If this is correct then do get somebody who has, to show you how to do it properly first. Not that there is anything particularly difficult about it ... but props can bite! and it's not simply a matter of
I'm sure you probably know that, but it seemed worth mentioning.
SS
From your posts I'm guessing that you've never swung any prop before. If this is correct then do get somebody who has, to show you how to do it properly first. Not that there is anything particularly difficult about it ... but props can bite! and it's not simply a matter of
"call "contact" (checking only the left mag is on), then give the prop a swing
SS
And fully respectful of them...
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From: Escapee from Ultima Thule
We handswung a C402 once while ferrying the bucket of bolts for maintenance. Lucky me: I was the pilot for the flight so got to do the cockpit bit while the big, burly engineer did the hard work...
Joined: Jan 1999
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From: Slowly decaying (disgracefully)
I used to regularly hand-swing a non-electric vagabond with a 65HP lycoming (I think) without problems. VWs are not too bad either. I once swung a Long-Eze (Lyc O-235) and ended-up with 2 broken fingers because the bod in the seat selected Both mags 
HFD
HFD
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From: Classified
I have witnessed a 600 hp (R-1340) radial hand swung, by one man. Easy when the engine is cold. Almost impossible when warm.
When the first "pot ignites" there is ample time to get out of the way, before the second blade arrives.
When the first "pot ignites" there is ample time to get out of the way, before the second blade arrives.
Joined: Dec 1999
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From: Oop North, UK
Starting the engine this way will not of course make the alternator charge a flat battery, so none of the electrics would work.
Joined: Mar 2000
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From: U.K.
There are a number of reasons, first of all the alternator needs some power to it otherwise it won't produce any power itself, secondly a flat battery often won't actually take a charge, especially if the plates have been knackered.
Trying to charge a totally flat battery can wipe out the alternator as well, often the relays can get burnt out and you then have not only a flat battery, but a stuffed alternator also.
Basically if you need to hand swing a prop, have a think about why, if the battery is just low due to lack of use and it's a cold day, then hand swining may be an idea, BUT if the battery is actually dead, then at least try and recharge it with a trickle charger before going flying. If it is toast, then replace it, don't muck about with hand swinging just to get in the air.
This is especially true of turbine a/c that use battery starts. The lower the inital voltage, the higher the chances of a hot start and all the associated (expensive) problems. I've seen a couple of people damage £50k turbine sections because they've been too tight to put in a new £400 battery. Very stupid!
Make sure you always have a good battery, don't try to 'get away' with a duff one, it's a false economy.
Trying to charge a totally flat battery can wipe out the alternator as well, often the relays can get burnt out and you then have not only a flat battery, but a stuffed alternator also.
Basically if you need to hand swing a prop, have a think about why, if the battery is just low due to lack of use and it's a cold day, then hand swining may be an idea, BUT if the battery is actually dead, then at least try and recharge it with a trickle charger before going flying. If it is toast, then replace it, don't muck about with hand swinging just to get in the air.
This is especially true of turbine a/c that use battery starts. The lower the inital voltage, the higher the chances of a hot start and all the associated (expensive) problems. I've seen a couple of people damage £50k turbine sections because they've been too tight to put in a new £400 battery. Very stupid!
Make sure you always have a good battery, don't try to 'get away' with a duff one, it's a false economy.
Avoid imitations
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From: Wandering the FIR and cyberspace often at highly unsociable times
An alternator needs a field current to "excite" the field coils, before it can produce any charge. This needs to be provided by the battery and if it is completely flat, no current might be produced even though the alternator spins as normal. The charge / ignition light on an alternator equipped machine is a critical part of the system - if it doesn't light before start, there is a fault because it shows no "exciting" charge to the field coils - it's connected in series.
Conversely - starting, then flying, an aircraft with an almost flat Ni-Cad battery by other means might not be a good idea because IF the alternator DOES charge, it might cause the battery to overheat due to the very high rate of charge that will result.
Conversely - starting, then flying, an aircraft with an almost flat Ni-Cad battery by other means might not be a good idea because IF the alternator DOES charge, it might cause the battery to overheat due to the very high rate of charge that will result.
Joined: Apr 2000
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From: 30 West
As my brother is rather old now and used to fly Shackletons for the Womens' Auxiliary Balloon Corps, he tells tales late at night over his Horlicks about sandbagging Shackletons down route. Not quite a hand swing but I would have liked to see it none the less.
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From: Midlands
“If the battery is actually dead, then at least try and recharge it with a trickle charger before going flying. If it is toast, then replace it, don't muck about with hand swinging just to get in the air.”
This is an exact replica of a conversation I had with an instructor when trying to hand start a DR400/160, my other aircraft was a Nipper with no electrics. He was adamant I should not fly the DR400. I could not see the problem provided I kept the alternator turned off. The flight went very well!
Rod1
This is an exact replica of a conversation I had with an instructor when trying to hand start a DR400/160, my other aircraft was a Nipper with no electrics. He was adamant I should not fly the DR400. I could not see the problem provided I kept the alternator turned off. The flight went very well!
Rod1