Mpunku (oz12306)

About this Plan

Mpunku. All-sheet balsa sports biplane model, for free flight or single channel RC.

Direct submission to Outerzone.

Update 28/12/2022: Added article, thanks to RFJ.

Quote: "All-sheet quickie for .049's - radio or free-flight. Mpunku
by AW Bennie.

The designer, who hails from S. Africa, tells us that 'Mpunku' is the local Xhosa (Bantu) word for 'Mouse.' THE original model was designed for calm evening flying but has since proved airworthy in quite stiff breezes, once its handling properties are learned. It was powered by an OS .06 - which is the maximum recommended power - sport .049s being quite satisfactory. It will handle a TD or Hornet, but the flying speed, which is essentially low, will not increase proportionately with power increases.

Construction: This is quite straightforward. All joints involving ply were made with Araldite on the original. If the builder gives the matter some thought and builds in a logical sequence, it is possible to complete Mpunku in one weekend - start Friday evening and the model can be airborne on the Sunday afternoon!

The nose formers and bearer arrangement can, of course, be adapted for radial mounted engines such as the Babe-Bee, Golden Bee or Cobra, but the 10 degree downthrust must be maintained.

Radio equipment in the original Mpunku was a Kraft valve receiver and Bonner Varicomp escapement giving an installation weight of 22-1/2 oz. With a relayless receiver and careful balsa selection 18 oz should be easy to achieve.

Finally, a cheering thought for those who have suffered in the past from the old biplane problem of 'where to hold it' when launching - the centre section ribs on the lower mainplane are both large in section and extended downwards a little: the launch is made gripping these ribs!"

Supplementary file notes

Article.

Corrections?

Did we get something wrong with these details about this plan (especially the datafile)? That happens sometimes. You can help us fix it.
Add a correction