P&W R1340 Engine mount - DHC3 Otter

[PBPouw]

I am working on the reverse engineering of a WW2 fighter. It's a Fokker G1 ( Netherlands - 1938 ). Originally this aircraft had Bristol engines, because of the difficulty to obtain and keep them running I am looking as an alternate the Pratt & Whitney R1340 S3H1-G. This engine is also used on the De Havilland Canada DHC3 Otter. They use a kind of dynafocal vibration mounts ( LORD ? ). Can anybody provide me with info , preverable drawings ? Anything is welcome.

Pim Pouw , the Netherlands

see link

http://www.xs4all.nl/~irmapim/motor.htm

 

[SAITAETGrad]

Try contacting Viking Air. They recently acquired the TC for the Otter and have all the production drawings.

 

[aviat]

The Lord Corporation made many engine vibration isolators for aircraft in North America, and even if other companies manufactured the isolators, they were still called Lord mounts. In other words the name became generic.

As far as getting drawings, being that it is a vendor product, only the OEM would have them, and for several reasons it is very unlikely that they would supply them to you. Even if you had them, I don’t know if they will help, because, for the price you can buy them, you couldn’t begin to make them. New Cal Aviation has many parts for the Otter and likely have the vibration isolators. Before you install the Otter isolators on your airframe though, I would check with Lord to see if that can be done. You may need different isolators. The second site has some design information for isolators.

http://www.applegate.co.uk/chemical/company/co_1008229.htm

http://www.lord.com/Default.aspx?tabid=833

http://newcalaviation.com/

Some food for thought!
The Otter is approved for both the S1G1-G and the S3H1-G engines. The major difference between them is the supercharger gear ratio. There are non-geared models of the R 1340 which are said to be better. Regardless, the engine was originally designed in 1924, and has not been changed for more than 50 years.
Have you looked at the PZL-1000 engine that is made in Poland? There is a STC to replace the R 1340 in the Otter with it. It has the advantage that it is still being made, but at 1000 hp may be more than you need.

http://www.airtechcanada.com/otter.html

 

[PBPouw]

Thanks both for the info,

Designing and buiding a replica aircraft have nothing to do with common sense. The engines and props ( sound ) have to look as close to the original as possible. The P&W is good in this sense because it can run the same 3 bladed counterweigth ajustable prop of the same diameter.

The vibration mounting apllied by DeHavilland was not their design, this came from P&W as an approved way of installing the R1340 ( I have the original installation manual ). The manual doesn't state the brand of the vibration mounting but the DeHavilland IPC does. Originally it was made by MB industries. I now have to figure out who fabricates them now.

Pim Pouw