Who designed it

From ‘Wings of the weird and wonderful vol 2’ by Capt Eric Brown

‘The Double Mamba is basically two side by side propeller turbine engines,each driving one prop through independent gear trains.The port engine drives the front prop.Each engine is a separate unit having its own fuel and oil systems,so that each one may be operated independently of the other.A common AUXILIARY gearbox is driven by either or both engines.’

He goes on to say that the first engine was started using a cartridge and normally the second was ‘windmill’ started whilst running the first engine at full power,although both engines had cartridge starters(saved on carts i suppose and probably a more reliable method of getting a good start!)
He also says that the Gannet was pleasant and stable to fly and a delight to land.

A long developement period for powerful turboprop aircraft was not unusual,even just the prop control systems were complex and quite a few military turboprop types failed to go into service successfully.

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The Douglas XB42 Mixmaster had two Allison V1710’s and according to some descriptions each engine drove a seperate propeller. Can anyone clarify the configeration.

According to Bill Gunston in AM of Sep 75 both engines fed into a common gearbox from which separate inner and outer shafts drove the propellers. Still a bit ambigious, although seemingly mitigating towards a common coupled drive system. Francillon,in the Putnam Douglas book, on the other hand, refers to the left powerplant driving the forward propeller and the right aft, which implies some form of decoupling having to be available in the case of a lost or seized engine.
Aircraft of the Fighting Powers Vol VII adds no more to that of Bill Gunston.
Did you have any other sources Pogno?

YouTube links:

Gannet Video 1
Gannet Video 2

Click links above.

849 Squadron B Flight normally located to RAF Lossiemouth during the 1970’s, when not aboard HMS Ark Royal.

or uncoupled to be precise. 🙂

IIRC, the Kuznetsov NK-12 turboprop, rated at 14,795shp, which powers the Tu-95 Bear, An-22 **** and Tu-114 Cleat has the same layout as the Double Mamba.

Two turbines driving the contra-rotating props through a gearbox.

I have been unable to confirm whether each turbine drove its own prop independently – but I am still looking………..

I would suspect that the Gannet was not the only ‘coupled-engine’ aircraft to reach production.

Ken

Getting away from the “Definition of Coupled” debate – did any of these “twinned engine” (as opposed to “twin engined”) projects produce efficient and reliable aircraft (apart from the Gannet)?

The Gannet (ASW) was also flown from HMAS Melbourne.

If you go to youtube .com and do a video search for “jets:fairey gannet” you`ll find two short clips on Gannets and the double Mamba. I`d insert the links but I`m too dumb.
I did see Gannets flying at an airshow at HMAS Albatross Nowra in my youth, and I still remember the ungodly noise they made.
Simmo

The Allison T-40 engine used on the Convair Pogo and Tradewinds was a coupled turboprop, produced by building two T-38 powerplants side-by-side, into a single gearbox, result 5,850 shaft horsepower turning two, 4.8 m (16 ft) diameter, counter-rotating propellers.
This again did not give the single engine redundancy that the Mamba had.

The Learfan had A couple of PT6’s driving through shafts to a single gearbox and propeller, so that doesnt count.

The Douglas XB42 Mixmaster had two Allison V1710’s and according to some descriptions each engine drove a seperate propeller. Can anyone clarify the configeration.

I suppose I was being a bit “loose” in describing the Double Mamba as being coupled but the point I was getting at was that I was assuming that the development of the Mamba/Double Mamba was what slowed the Gannet’s entry into service.

Is that a correct assumption?

I agree, the engines were not coupled. Each Mamba drove one propellor and couldn’t drive the other. One unit yes, hence Double Mamba as opposed to two singles, but they were totally independent.

Roger

My point is that the engines were not coupled together but operated independenlty of each other. They were two independent engine/gearbox/propellor units even though they were held together by a common housing.
Unlike,for example the Bell 212 helicopter which has two engines driving one gearbox/powertrain – in this case the engines are ‘coupled’ via the gearbox.

Or have I got hold of the wrong end of the stick? :confused:

CS

Was the Double Mamba a coupled engine?

I think that the powerplant was called a Double Mamba because both Mamba engines were attached to the common gearbox casing. CS

CS I think youv’e answered your own question – the two engines were coupled via the gearbox. I think the manufacturers regarded it as a single unit.

Roger Smith.

From H.A.Taylor’s Putnam book “Fairey Aircraft since 1915”

“the Q – designed by a team under H.E.Chaplin, Fairey’s chief designer, and D.L.Hollis Williams, chief engineer…” the Gannet was originally designated the Fairey Q or 17.

When I wer’ a lad and in the ATC we had a Flt Sgt Bruce Randle who built a control-line scale model of a Gannet. It, like the full size one, had two model engines driving the two propellors and, with the third line, could stop (and re-start I think) one of the engines as well as lowering/raising the u/c and arrester hook. He won the international Knokke Trophy with it.

I don’t suppose three constitutes ‘production’ but the Saro Princesses were powered by 10 Bristol Proteus engines – eight of them coupled in four pairs.

Roger Smith.

Was the Double Mamba a coupled engine?

I thought that it was two separate Mamba engines driving separate gearboxes housed in a common casing and driving separate propellors. One engine could not drive both propellors. Thus to extend the loiter range of the Gannet, one engine would be shut down and the associated propellor feathered.

I think that the powerplant was called a Double Mamba because both Mamba engines were attached to the common gearbox casing.

I also think that the Brabazon engines worked the same way – one Proteus drove its own gearbox/propellor although both gearboxes were housed in a common casing.

I stand to be corrected though.

CS

That makes sense about the extende into service time. I don’t think the Manchester had coupled engines, I thought it was 2xRR Vultures which as I recall were H 24 layout. The only other aircraft I can think of with coupled engines was the Bristol Brabazon apart from the He177.
Just been looking the Gannet up on wikipedia and it doesn’t even give the designer on there though the entry for the Gloster Javelin does, could it be no one remembers?

They had some initial directional stability problems which is why those small fins were fitted to the tailplanes.

The big “slower upper” must have been the Double Mamba turboprop. Coupled engines are always trouble and the Mamba was almost unique to the Gannet, so the Gannet would have borne the brunt of any Double Mamba development problems.

Would I be right in suggesting that the Gannet was the only “coupled engine” aircraft to reach production AND have a successful career? The only other iarcraft with coupled engines that I can think of that reached production but which were notoriously unreliable were the Avro Manchester and Heinkel He177.

All other coupled engine projects never went beyond the prototype or test phase.

Sooo, I was 2 when she first flew and 7 when she entered service. Seems a long development period for aircraft of that era. Any ideas what took them so long?

The Gannet first flew in 1949 and entered service with the Navy in 1954.

Can’t name the original designer but it was initially used as a carrier based anti-submarine aircraft. The version in the picture is the later Airborne Early Warning variant used by the Royal Navy up to 1978.

The Gannet is not that unknown an aircraft, having served with the Royal Navy for almost 25 years.

I’ve always loved the Gannet in its ASW variant but not so keen on the AEW. What the hell it’s still a Gannet. What I still don’t understand is why I love them.
I didn’t realise that they were in service that long.