This AV is strictly for the purpose of uploading a custom engine sound. Otherwise the aircraft is stock except for two changes necessary for the proper integration of the engine sound profile and those are propeller size and engine torque.

This is the ASP 'FS400AR' five cylinder radial glow fuel engine. It is 64cc or 4.0 cu in. The specifications are as follows:

Features and Technical Data
• 5 cylinders, arranged radially (72°)
• four stroke system
• cubic capacity per cylinder: ~12.8ccm
• bore hole x stroke: 26.5mm x 23.2mm
• power: 4.08kW at approx. 7250 rpm
• weight: 2.8kg incl. mounting
• engine rpm range: approx. 800 to 9000 rpm

Propeller Selection
What propeller is to be used depends on the size and the weight of the plane and the desired
flight properties. Therefore, we cannot give a general recommendation here.
The following revolutions per minute will be achieved approximately:
Propeller Rpm
18 x 10 8200-8400
18 x 12 7200-7400
18 x 14 6800-7000
20 x 8 7900-8100
20 x 10 7000-7200
22 x 8 6900-7100

The sound recordings are taken of my own personal engine, and according to the tutorial by Knife Edge using the 'Audacity' software the profile for the sim was created.

Thanks to 'csgill' as well for his tutorial.

I recommend adjusting the engine volume in the 'Settings' from the default output of 85% down to 70% when using this model.

For the best effect, try to fly the Sopwith scale like. I.E. slow, at around 4600 RPM.