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diddy1234
19th May 2008, 12:48
I was wondering if anyone knew the mechanics / methods of starting engines on prop aircraft.

I have noticed that the pilots turn over the engines with no mgneto's turned on, is this to drag in fuel into the cylinder chambers ?

then engage the magneto's and start the engine.

But If i look at a video on you tube of a corsair starting it seems different to other prop aircraft.

for example :-

http://www.youtube.com/watch?v=_VmxkpgiURA

The description with this video does answer some questions.

BTW, I love the engine idling on this video. very impressive bubbling sound.
With it had a supercharger fitted. That would make my day. LOL

On some prop aircraft I can hear the starter motor running up (as if its turning a large flywheel) then once spinning very fast, the engine is engaged to the flywheel and it starts. This is probably a completely wrong explanation so please correct me.

On the larger engines (with high compression) was there any other methods for starting the engines, like compressed air ?

RD

Aaaaaaaaaaaaaaaargh!
19th May 2008, 14:05
Cartridge starting like on the Flight of the Phoenix :8

"but we only have three left"

Dan Winterland
19th May 2008, 14:19
Priming the engine is common with some start systems such as a cartridge start which gives you only a couple of rotations, so you have to be ready for it. Some radials also have a habit of draining oil into the bottom cylinders which could break the pistons through hydraullic lock which can be negated by turning the engine over by hand to drain the oil when the valves open.

The inertia starter involved storing energy in a flywheel prior to engaging it. This energising can be done by an electric motor (Harvard) or by hand cranking (Me 109).

Compressed air is used in some engines such a the Russian made Yaks.

And of course, there is hand swinging.

Shaggy Sheep Driver
19th May 2008, 19:44
Hydraulic locking will usually bend a con rod. If you're lucky, the engine will fail there and then. If you're not, it will fail some time later, in flight. Happened to a guy in the US in a Yak 14T - he didn't survive.

Pulling the prop through on a Vendeneyev (like what Yaks have) won't get all the oil out if it's not run for quite a while as the inlet pipes from the supercharger have a low point which is lower than the valve seats. You have to remove the drain plugs in the inlet pipes of the lower 3 cylinders. The Vendeneyev has a pneumatic start system - compressed air is admitted to the cylinders via an air distributer to turn the engine while a 'shower of sparks' magneto is operating.

The Gipsy Major engine in our Chippy is primed by flooding fuel into the inlet manifold and pulling the prop through 4 compressions.

con-pilot
19th May 2008, 19:45
Hi Dan.

by turning the engine over by hand to drain the oil when the valves open.

Although it has been a lot time since I have flown an radial engined aircraft, the DC-3, we were told not to pull the prop through by hand as this could cause internal engine damage. It was recommended to use the starter because the clutch will slip before enough torque is applied to damage the engine.

We need to ask pigboat, I will happily accept his answer on this subject.

I could be wrong and it would not take much for me to change my opinion.

Take care, C-P

Shaggy Sheep Driver
19th May 2008, 19:47
You certainly have to pull a Vendeneyev through - and it's hard work! No starter clutch - it's pneumatic - see my post above. If a while since it ran, even pulling through aint enough.

411A
19th May 2008, 20:14
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).:ok:

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.

aviate1138
19th May 2008, 20:16
AN-2

http://www.youtube.com/watch?v=BxhSmeAqD0g

I want one........

Be patient, he does fire it up eventually.....

ATNotts
20th May 2008, 18:35
Moving forward a bit in time, I remember from my youth watching Britanias (102s and 312s) start up at BHX.

Before each engine was started an engineer rotated the prop, a couple of times I think. I can't recall seeing any other turbo-prop being started in this way, and I can't imagine the SRN-4 Hovercraft (which IIRC also had 4 x Proteus engines) having the props swung.

Can any former Britannia crew enlighten me as to what the purpose was of turning the props before fireing the engines up - and I mean fireing, I will never forget those wet starts!

pigboat
20th May 2008, 23:45
Although it has been a lot time since I have flown an radial engined aircraft, the DC-3, we were told not to pull the prop through by hand as this could cause internal engine damage. It was recommended to use the starter because the clutch will slip before enough torque is applied to damage the engine.


That's what we were taught also.

I've flown the R985 with the inertia starter. It's somewhat disconcerting floating down a river right above a falls while waiting for that fershlugginer flywheel to wind up to speed, particularly when you had told the sub-moron onshore to hold onto the aircraft until you had the engine fired up. :ooh:

You could cross start the PBY on the water with a rope if you blew a starter. Wind one end of your rope around the prop dome of the engine with the operative starter and the other end around the dome of the engine to be started, making sure the rope went either under the dome or over the dome, depending on which engine was to be started. Set up the engine controls and prime on the bad engine, then motor over the good engine with the mags off which turned the bad engine. You had to be right quick after the rope ran off the bad dome to hit the mags on the bad engine, otherwise it meant commencing the whole operation again. Not that I've ever done that mind you, I just heard it could be done. :p

A DC-3 could be started with a rope also. It required either one pickup truck, two snowmobiles or five men and three little boys. And don't worry, there were always three little boys standing around ready to pull on the rope. :D

Blacksheep
21st May 2008, 06:12
Before each engine was started an engineer rotated the prop, a couple of times I think.You also had to hold the blades until the engine produced enough torque to turn them in the right direction, then let go. A weird and wonderful beast was the Britannia.

diddy1234
21st May 2008, 07:41
Blacksheep (http://www.pprune.org/forums/member.php?u=2325) I didnt know turbo prop engines were that free running.
I thought the gearing would prevent windmilling of the prop in the wind.

The Bristol Britania, what a sight. I used to see them fly in to my local airport when I was younger.

I only recently found out how free running the welland engine is (Dehavilland museum in St. Albans).

I always thought that alot of inertia was needed to turn these engines hence they wouldn't windmill in the wind easily. Obviously I was wrong.

blue up
21st May 2008, 08:00
http://s82.photobucket.com/albums/j279/foggythomas/?action=view&current=FredEngineRunFFF06-1.flv

http://s82.photobucket.com/albums/j279/foggythomas/?action=view&current=2005_1011Image0022.flv

Some easier than others. Modern (?) electronic ignition makes it easier to start due to variable ignition timing but the homebuilt radial on G-BMOO needs a huck-starter to spin it up enough to run. G-BMMF can now be started with the use of a little finger to push it past the TDC position (on a good day).

justlooking_tks
21st May 2008, 10:39
Yes, an old radial engine like most piston a/c engines was much easier to start when cold. You can and I have, hand proped a cool engine but no way can you do it when hot. Quiet safe really as she started to splutter and bang and turn you were well out of the way before the next blade followed through.

When cold, we used to turn the PW 1830 engine by hand, at least 6 revolutions to check for a hydraulic lock. 1st revolution was a gentle turn in case you had what you were looking for, I.E. Then prime with hand pump to gain fuel pressure. Unlock hand primer and give it 5 shots if IIRC and about 5 pumps on the throttle. Engage starter motor, inertial, when you had 4 blades past, ignition to both. When she began to wease, pop, fire and belch smoke everywhere, it was a case of pumping/controlling throttle with one hand and priming with the other until the engine began to turn over evenly, then lock up the primer.

When hot, it was just a matter of pumping up the fuel pressure, one or two pumps on the throttle, engage starter and once turning ignition to both.

It was important that you did not over prime the engine as it could cause a fire on start up. If you saw flames or someone saw them on the ground the important thing was to keep the engine running or turning.

This was from 30 years ago so my memory may have faded a bit.

Windy Militant
21st May 2008, 13:07
The Gipsy Major engine in our Chippy is primed by flooding fuel into the inlet manifold and pulling the prop through 4 compressions.
and when that doesn't work resort to the
FAILSAFE STARTING PROCEDURE
Switches off, throttle
closed.
Tickle fuel pumps.
Suck in 4 blades.
Throttle wide open.
Reverse 16 blades.
Throttle closed.
1 blade forwards.
Now try swinging it with the mags on.
And if that doesn't work get a couple of riggers to hold the tail up so that all the cylinders get an even amount of priming.
If that doesn't work, retire to the bar! ;)

LFittNI
21st May 2008, 15:12
The only reason to make sure the prop actually turned was to ensure that the prop brake was off prior to starting......otherwise you had a very upset Flight Eng.

Then, when the brake was off, the prop had to be held (not turned), in case the prevailing wind tried to turn it the wrong way.

And yes, Proteus wet starts were great fun!

pigboat
21st May 2008, 15:56
I had a friend who used to work the ramp in Boston many years ago. One of his favourite tricks was to hold the prop of either #2 or #3 engine while the engine was being started. Then with the passengers peering out the window, he'd flip the prop and watch the looks on their faces when the prop began to spool up. :D

ATNotts
21st May 2008, 18:09
LFittNI

Thanks, very informative. To a spotty faced 11 year old it appeared as though the ground engineer was actually turning the prop, rather than holding it back.

Must get to Kemble the next time they wind up their Brit.

Shaggy Sheep Driver
21st May 2008, 19:22
and when that doesn't work resort to the
FAILSAFE STARTING PROCEDURE
Switches off, throttle
closed.
Tickle fuel pumps.
Suck in 4 blades.
Throttle wide open.
Reverse 16 blades.
Throttle closed.
1 blade forwards.
Now try swinging it with the mags on.
And if that doesn't work get a couple of riggers to hold the tail up so that all the cylinders get an even amount of priming.
If that doesn't work, retire to the bar!


Sort of....

No need to suck in and then blow out... If it hasn't started after tickling and priming and a few 'swings', it might need blowing out - mags off, throttle wide open, prop backwards. Then try it.

If it doesn't start then, re-prime and try it one swing. If still no go, suck in 4 compressions and try it.

But none of the above will work if the impulse is stuck - listen for that 'click' as you pull it over. If no click, whack the RH mag (as seen from the cockpit) with your shoe. It should then 'click', and will start!

Only once ever had to use the 'tail up' method. It was a very cold morning, and the fuel in the inlet manifold wasn't vapourising enough to reach the front 3 cylinders. Engineers held the tail up to get the aeroplane level to get all 4 cyclinders adjacent to the fuel in the manifold, and she started first swing!

SSD

taxydual
21st May 2008, 22:16
Wasn't there a story about a C-130 with dud starter's on the port engines, and another C-130 being towed into such a position so that propwash from the second C-130 starboard engines 'bump started' the first C-130's port engines? If you see what I mean.

Urban myth?

Aaaaaaaaaaaaaaaargh!
21st May 2008, 22:43
No but there's a (true) story of someone trying to take off in a 337 with an inop starter on the rear engine. He figured he could get it turning on the take off roll and start it that way.

Sadly, he was wrong :(

Maybe it was this one http://ntsb.gov/ntsb/brief.asp?ev_id=20001212X21134&key=1

ZH875
21st May 2008, 23:00
Wasn't there a story about a C-130 with dud starter's on the port engines, and another C-130 being towed into such a position so that propwash from the second C-130 starboard engines 'bump started' the first C-130's port engines? If you see what I mean.

Urban myth?

That is possible on the T56 Engined Hercs, and has been done, but on the newer J model Hercs with the AE2100D3 engines, that is not possible due to the free turbine. (Prop will spin but not the required engine bits)

Each J Herc can carry a 'Buddy Hose' which when connected to another 'Buddy Hose' will allow bleed air from one aircraft to start the engine on the other. Two hoses are required due to the distances involved.

Chris Scott
22nd May 2008, 00:18
Quote from ATNotts:
Must get to Kemble the next time they wind up their Brit.
[Unquote]

That's news. Could you PM me in advance, please? The sound of a taxiing Britannia must be unique.

denis555
22nd May 2008, 07:53
Cartridge starting like on the Flight of the Phoenix :8

"but we only have three left"has anyone got a link to a video of an a/c being started with the cartridge method ( as in Flight of the Phoenix?) I have looked on youtube to no avail.

ps Does everyone agree that the remake of FotP was t-e-r-r-i-b-l-e? Why didn't they just give Dolly Parton the role of Pilot (flying in a cowboy hat y'all) and Sly Stallone the role of chief engineer in Rambo gear if they wanted to mess it up so much?

bluesafari
22nd May 2008, 16:28
I remember being on Labuan in mid 60s when a FAA Gannet stopped by, when they couldn't get the engine started a Twin Pioneer was wheeled out and a start by wind-milling was attempted without sucess, then the Valetta was tried, still no go, then a Shackleton was tried, but not enough speed to get a start, in the end they had to wait for an underwing start pod (Palouste ??) to be flown in.
Happy days ! !

Compass Call
22nd May 2008, 19:58
taxydual

A Strikemaster has been used to start the port inner on a Boeing 707. Masirah circa 1980 when no air start trolley was available:ok:

CC

eagle 86
23rd May 2008, 00:48
My experience with an "old" engine, R1820 in T28 1966, was to turn engine over, count three blades (hyd lock) tickle primers, when it fired on primers advance mixture to full rich - clouds of lovely blue/grey smoke and a satisfying hiccupping rumble!!
GAGS
E86

NutLoose
27th May 2008, 00:27
Believe it or not they have hand swung a DAK engine during the war, it involved several men and a load of innertubes linked together and thrown over a blade.... gulp !