Cranking Question

[denis555]

I was watching a documentary on Adolf Galand which showed two 'Erks' hand cranking a Bf109 to get it started.

I recall similar tactics used ( with a very small handle which seemed fit only to start a lawn mower ) used on the Spitfire.

Since my only experience of cranking an engine with a starter handle was with a Morris Minor - I remember how physically tiring that was.

If 1000cc and four cylinders was hard enough how on earth did two people have the strength to crank a massive V12 Spitfire lump???

Anyone had experience of this?

[Dan Winterland]

It was an inertia starter. A flywheel was got up to speed by hand cranking, then a clutch was engaged and the hopefully, the kinetic energy in the rotating flywheel had enough oomph to start the engine. Other inertia systems had an electric motor to energise the flywheel. The NA Harvard had/has such a system where an electric switch was moved one way to spin up the flywheel. Once the 'hum' had stabilised, the switch was moved the opposite way to engage the clutch.

Later Merlin powered Spitfires had conventional electric starters. Griffon powered Spitfires had cartridge starters.

[denis555]

Ah I should have realised that it used inertia -thanks.

Mind you it must have needed some muscle to get the inertia wheel up to speed?

[stevef]

I've done manual inertia starts on Dakotas (pre-direct drive days) and a PT17. They sure warm you up on a cold morning. :)

[India Four Two]

Google "fairey swordfish inertia starter" and have a look at the extract that comes up in the first listing
From the Flight Deck: An Anthology of the Best Writing on Carrier (http://books.google.ca/books?id=G-3WfV1gp9wC&pg=RA1-PA44&lpg=RA1-PA44&dq=fairey+swordfish+inertia+starter&source=bl&ots=IYUOkQjsSo&sig=MlV7_D6oSFQ_IkGcWNLm_mrOh0k&hl=en&ei=i3rtSazlNqb06gOv3cDNAw&sa=X&oi=book_result&ct=result&resnum=1)


A good description of the inertia starting process, leading into the Taranto raid.

I remember reading in another book about a crew becoming exhausted trying to start the Swordfish of a new pilot. Eventually, the Petty Officer climbs up to the cockpit, looks around and then pointedly switches the mags on!

[denis555]

Thanks I42 - interesting link.