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View Full Version : Tiger Moth starting procedure - Standing in front or to the rear of the propeller


Tee Emm
29th Mar 2011, 14:27
When I first flew RAAF Tiger Moths (1951) the starting procedure was based upon the airman ground staff member standing in front of the propeller. Hand starting of numerous similar light aircraft was the same - invariably with the person turning the propeller standing in front of the prop.

Watching Tiger Moth joy flights at a local aerodrome in Victoria, Australia I noticed that the person starting the Tiger Moth now stands at the back of the propeller rather than the front. This appears to be common practice nowadays. One opinion is that it enables the starter person to reach the ignition switches more easily if the aircraft moves forward. On the other hand, it seems from observation that the aircraft lower wing could push the starter person into the arc of the propeller if the aircraft was to move forward under its own power.

I have a rare copy of the Royal Air Force Flying Training Manual -Part 1 -Landplanes. It is called Air Publication 129 revised 1937. Chapter 2, illustrations 64 to 67 show what appears to be a Miles Magister (?) two seat monoplane being started and in each photo the starting airman is in front of the propeller.

The original method of standing in front of the prop seems much safer since if the aircraft moves forward it is easier for the prop swinger to move out of the way to one side. When and why did the procedure change?

Booglebox
29th Mar 2011, 22:35
I wouldn't do that if paid good money - limited space, fuselage getting in the way, etc. Front facing is not ideal either (if a/c jumps chocks, possible suction effect I guess if a/c is somehow at full throttle) but I reckon it's certainly better, with less probability of something going wrong, than the alternative!

Also, the Tiger and also its engine was designed with hand-starting in mind, and people have been doing it that way for many many years, so why change it? (however if someone can come up with a good reason I would be interested!)

FullOppositeRudder
30th Mar 2011, 00:29
As ground crew when we worked with one as a glider tug, I always swung the Auster from behind the prop. Being a right hander it seemed easier and safer as the natural body action turned one away from the fuselage and outside of the arc of the propeller as the swing progressed.

The pilot was always at the controls during this process anyway. It was also easier to initiate the priming process from behind the prop on that side of the fuse'; this seemed to be nearly always necessary, the precise recipe varying with almost every start - and who was flying it.

It's been a long while ago now but that's my recollection, possibly dulled by long hours at the bar in that era.:E

How things have changed.

FWIW
FOR

glhcarl
30th Mar 2011, 00:54
Ground crew? I first started flying with my brother-in-law in his Luscomb 8A, when I was 12. We would un-tie the wings. I would work the magneto, throttle, choke and hold the brakes while he spun the prop "from the front". Once the engine was running smoothly he would un-tie the tail wheel, get in and off we would go. Things were so much simpler 50 years ago.

Air Tourer
30th Mar 2011, 02:22
I was taught to clear the cyl by winding backwards from the front, prime it with fuel by winding it forward from the front, and then go to the back to start it. Presumably the handy front cockpit switches are there for the starter to turn them off if the prop needs a reposition for the next swing. If not, why are they there?

Brian Abraham
30th Mar 2011, 06:38
Just be careful.

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JohnMcGhie
30th Mar 2011, 07:00
I was taught to swing Tigers (and everything else that needed swinging...) from the front. This enabled you to pull your arm down and walk across the aircraft nose and out of the propeller arc.

Even if you miss your footing in a lumpy grass paddock and the engine catches on the first swing, you will still fall out of harm's way.

There was some other aircraft that we used as a glider tug that had to be swing from behind (or left-handed...) which I always tried to avoid. If your hand slips, you end up with your neck in the chopping arc and the wing preventing a hasty retreat. That would be the time the engine catches first go, right?

Yes, I was taught that you had to swing backwards first to ensure no cylinders had a hydraulic lock as a result of oil moving past the rings into the upside-down cylinders, which would bend the crankshaft if it fired in that condition.

You only had to prime for a cold start (i.e. if the cylinders were not warm to the touch, you needed to prime). But this was Christchurch, New Zealand (Wigram...) where the ambient air temperature was fairly low...

It was "rumoured" that a pilot could self-start a Tiger without being in the cockpit during starting. It was also rumoured that the CFI would be clearly audible above the running engine, and potentially also at the other end of the runway, if he saw anyone attempting this. So we didn't...

Memories...

Shaggy Sheep Driver
30th Mar 2011, 22:03
From the front. Same with the Chippy. The only aeroplane I swing from behind the prop is the J3 / L4 Cub (engine rotates the other way, so it suits a right hander - and your left hand can be on the mag switches in the cockpit).

Exaviator
31st Mar 2011, 01:32
For a right handed person the safest way is to swing a prop is from the front for an engine which rotates clockwise (Looking from the front) i.e. the Gypsy Major and from the rear for an engine which rotates anti-clockwise. i.e. Lycoming.

For a Tiger or Chippy:

Prop blade in the 2 o-clock position, both hands on the training edge of the prop, pull down against compression and follow through by moving your body in the same direction. As the prop reaches the 6 o-clock and fires, or kicks back your hands and body should be clear of the path of rotation.

Did about 300 hours combined on those two aircraft and it worked for me, but was a lot younger then :ok:

Tee Emm
31st Mar 2011, 01:50
Thanks for the replies. I watch with great concern at pilots who hand start Cessna 172 and their ilk when faced with a flat battery. Talk about sheer complacency and poor airmanship. Some flying school operators are so money hungry they continue to fly their aircraft using hand starting of the propeller rather than delay and have the battery charged.

A year or so ago at an Australian flying school in Victoria, the CFI directed a new flying instructor to hand start a Cessna 172 that had a flat battery. The aircraft had been in that condition for several flights before. The instructor had never received dual instruction on hand starting. The inevitable happened and the student pilot in the aircraft left the mageneto key in the ON position when it should have been OFF. The instructor was struck by the propeller as he was turning it. Fortunately his injuries were not serious. A fraction of a second later and he could have been killed.

osmosis
31st Mar 2011, 03:43
I'm glad someone else has mentioned other aircraft, but the nosewheel configured are less hazardlous than tailwheels. I'm thinking of C180/185 series with flat battery. Long 2 bladed prop leaning back. As the prop reaches 12:00-6:00 position or so the prop swinger now has to push UP. Doing so forces him to step closer to the danger area. As pretty much usually happens, it tends not to catch on the safer downpull. Always the much more hazardous pushup. A real trap for the unwary.

Shaggy Sheep Driver
31st Mar 2011, 17:10
There's a lot of misunderstanding about prop swinging. But both the swinger (who is the guy in charge at all times) and the cockpit occupant (who follows the swinger's instructions at all times) need to be fully and correctly trained. It's not at all difficult, but there's stuff you MUST get right or it can be dangerous.

And the engine doesn't burst into life immediatly, threatening to chop off your hand. As you swing you step away, the engine 'catches', continues to rotate, and it's a couple of seconds before all cylinders join in and it's up to tickover speed. By then the swinger is (or should be) quite a long way away from the prop arc.

Minor injuries are sometimes caused by the engine firing before top dead centre and flicking backwards while the swinger's hand is still on the prop. Ensuring only the mag with the impulse on it is switched on will prevent this, and not curling your fingers around the prop's trailing edge will ensure that even if it does happen, no injuries should result.