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Al Timita
6th Feb 2011, 22:41
This is a question for the older pilots who flew piston engined aircraft for Australian based airlines (or the RAAF VIP squadron):

Was starting by cartridges ever used by old piston engined airline aircraft (CV340/DC3/DC4 etc) in Australia and, if so, roughly when were they converted to electric starting?

Thanks for stretching your memory banks

Mach E Avelli
6th Feb 2011, 23:13
The DC3s here were mostly converted C47s. The Aussie ones all had electric-only starters. Some Pommy and Canadian aircraft still had the wartime inertia crank starters fitted as a back-up.

Brian Abraham
7th Feb 2011, 00:27
As far as this aging memory remembers cartridge starters were a military thing. Not aware of any civil, or military adapted civil aircraft using cartridges. Used on some Spitfires, Canberra, Sea Fury, Venom etc - oh, and the military Chipmunk. Seemed to be a British thing as I can't recall any US aircraft using the system.

BBMouse
7th Feb 2011, 02:17
vaught or goodyear (cant remember which one, maybe both) corsair

Brian Abraham
7th Feb 2011, 04:22
BBM, you are quite right. Cartridge on the F4U until the -1C/D models when they changed to electric. Unbeknown to me till now is that it was the favoured method of starting by the US Navy up to 1943-44 when they decided direct cranking electric was the way forward.

The system was designed by Coffman (British) and manufactured in the US under licence by Breeze.

ForkTailedDrKiller
7th Feb 2011, 04:52
Featured big in "Flight of the Phoenix"!

Dr :8

T28D
7th Feb 2011, 05:21
Some Chipmunks had a "cartridge" start the cartridge was similar to a 12g Shot gun cartridge, and the Canberra Bomber has still got cartridge start for the Avon's.

TBM-Legend
7th Feb 2011, 09:13
USAF Martin B-57 used cartridge start...
F-4/KC-135/B-52 are other examples that used cartridges.


The Coffman engine starter (also known as a "shotgun starter") was a starting system used on many piston engines in aircraft and armored vehicles of the 1930s and 1940s. The Coffman system was one of the most common brands; another was the Breeze cartridge system, which was produced under Coffman patents. Most American military aircraft and tanks which used radial engines were equipped with this system. Similarly, the British Supermarine Spitfire used the Coffman system to start its Rolls-Royce Merlin engine.[1] The Hawker Typhoon also used the Coffman system to start its Napier Sabre engine.

A derivation of the Coffman starter was used on a number of jet engines, including such engines as the Rolls-Royce Avon, which were used in the English Electric Canberra and Hawker Hunter.



The Coffman device used a large blank cartridge containing Cordite that, when fired, pushed a piston forward. A screw thread driven by the piston engaged with the engine turning it over.[2] This was in contrast with other type of cartridge starter which acted directly to drive the engine piston down and so turn the rest of the engine over, such as those used on the Field Marshall agricultural diesel engines.

The other systems used during the period were electric motors (such as those used in automobiles today), inertia starters (cranked either by hand or an electric motor) and compressed-air starters, which operated much like Coffman starters but were powered by pressurized air tanks.

Shotgun starters are composed of a breech, into which the cartridge is inserted, which is connected to the motor by a short steel pipe, which acts like a gun barrel. The blank cartridge fits into the breech, and is triggered either electrically or mechanically. When the aircraft's ignition is turned on and the cartridge is fired, high-velocity, high-pressure gas (~1000 psi at ~600 ft/s) shoots down the pipe, forcing the motor to spin and engage the starter ring gear on the engine, which is attached to the crankshaft.

Shotgun starters had several advantages over other starting systems in use at the time. Electric starters required large, heavy, and often troublesome batteries to be carried on board, or external charging equipment had to be located at every place where the vehicle was anticipated to operate. Inertia starters used a heavy wheel, usually made of brass, which was spun by a hand crank or electric motor, causing the spinning wheel to engage the starter ring gear. The Coffman system was more lightweight and compact than inertial starters or internal batteries, and it did not require any special auxiliary equipment, an important feature when operating in remote areas.

The primary disadvantages of the shotgun starter are the need to keep a stock of cartridges, one of which is used for each attempt to start, and the short time that the motor is spun by each cartridge. Compressed-air starters, which use the same type of motor, are usually recharged by an engine-driven compressor, negating the need to carry cartridges, but adding requirements for the compressor and air tank. Hybrid systems can be made simply by adding a cartridge breech or an air tank to an existing system. Air tanks can also be recharged from an external source in an emergency, such as a hand pump or a portable air compressor.

The Coffman starter was the most common brand of cartridge starters during the mid-1930s, and the name was used as a generic description. Some modern military diesel engines still use this device, but advances in battery technology have made shotgun starters obsolete for most uses.[citation needed]

Old Fella
7th Feb 2011, 10:12
The RR Avon on the Canberra used either a Single Breech or Triple Breech Cartridge Starter. The Starter Cartridge used a cordite material and when fired, used a CONTROLLED RATE of burn. A metal bridging piece in the cartridge depressed a mushroom valve opening porting to a turbine which accelerated to around 44000 RPM and through a reduction gearing drove the engine. As the engine became self sustaining the engine RPM exceeded the starter RPM and the clutch dis-engaged. The starters were reliable and gave little trouble in service.

SgtBundy
7th Feb 2011, 10:52
I just happened to watch a documentary on the Canberra (B-57 to be exact) and was intrigued by the cartridge system. The large belch of black smoke at start seemed somewhat excessive, and the narrator commented inexperienced ground crews would sometimes extinguish the engines thinking they were on fire :ooh:

bankrunner
7th Feb 2011, 12:18
SgtBundy, if you ever get a chance, get down to Temora and watch them start their Canberra.

The belch of smoke and the associated bang is indeed a sight to behold.

The Canberra is also suprisingly quiet in flight. The Viet Cong wouldn't have known what hit them :E

Dora-9
10th Feb 2011, 10:05
T28D - ALL Chipmunks in UK military service had cartridge starters.

blackburn
10th Feb 2011, 11:27
Mach - The DC3s here were mostly converted C47s. The Aussie ones all had electric-only starters. Some Pommy and Canadian aircraft still had the wartime inertia crank starters fitted as a back-up.

There is one regularly used ex RAAF DC3 in Melbourne that has inertia starters as the only electric starting system. Maybe that is what you meant. It also has the ability to be hand cranked to energise the inertia starter system in the event of a depleted battery.

Blackburn

sixtiesrelic
10th Feb 2011, 20:22
There was a Chippie from Victoria that had a cartridge starter. We saw it operate at a Kingaroy Fun in the Sun? fly-in in the seventies or early eighties.

T28D
10th Feb 2011, 21:51
Then there is the really close relative the IPN starter where the cartridge was replaced by liquid Iso Propyl Nitrare which also gave the dramatic high energy " Expolosive" type start, the Sabre and Venom had this system,

onetrack
11th Feb 2011, 03:56
Here's the way to quick-start your recalcitrant radial, when you've run out of cartridges/battery power/air. No doubt, a method fully approved by all aviation authorities, worldwide... :suspect: :D

YouTube - Cold Start 9 cyl diesel radial engine (http://www.youtube.com/watch?v=zGLVtA3LHlE)

Super Cecil
11th Feb 2011, 05:14
Have heard of a radial on a certain eastern block AG aircraft being started with a yoot (In this country). The rope was wound around each blade individually, just inboard from the tip. Story goes it started.:8 Wouldn't wanna be drivin the yoot.

the nz green goblin
11th Feb 2011, 05:58
Super Cecil: Yoot may be spelt that way in your country, but elsewhere it is spelt Ute, which is an abbreviation for Utility.

aroa
11th Feb 2011, 06:07
One person that I know of has been busted by The Unmentionable, for putting a shot of "Aerostart"(tm) in the intake of a Robbie, on a cold morning.

Maybe the name is a misnomer..!!

Metro man
11th Feb 2011, 07:39
The Canberra is also suprisingly quiet in flight. The Viet Cong wouldn't have known what hit them

During the Rhodesian war in the 1970s Canberras were used against terrorist bases in Zambia and Mozambique. Monkeys (with superior hearing to humans) at these bases which had previously experienced a bombing raid would become very agitated at the sound of Canberra engines and could be relied on to give a few extra seconds of warning before the bombs came raining down.

The Rhodesian Air Force developed a method of starting the Canberra engines using compressed air which gave considerable cost savings over the cartridges.

Super Cecil
11th Feb 2011, 10:08
Super Cecil: Yoot may be spelt that way in your country, but elsewhere it is spelt Ute, which is an abbreviation for Utility.
Yes but in your country it's pronounced Yotulatea :8
And thanks for the spellenk lesson UNZUD GG, you have started your pwune career well, the onlly thingk you could doo would be grammer (Check that one fella) corrections. Thanks again UNZUD GG

mvd71
12th Feb 2011, 03:34
When I was working on a Venom, we had two dive bottles running through a Tee piece and into a modified cartridge cover on the starter to enable the use of compressor air. It worked well, and saved the cartridges.:ok:

Wunwing
15th Feb 2011, 09:56
The Australian RAAF and RAN C47s had electric/inertia starters fitted. The civilianised C47s and production DC3s had straight electric starters. You can tell the difference during start because you can hear the initia system winding up before the prop begins to turn.

So to answer the original question, the ex VIP, RAAF aircraft were fitted with electric/inertia starters.

For those of you heading off to Avalon, have a listen to the HARS C47 during start and compare it to any of the other DC3s around over the show.

Wunwing