Christer Landberg's 1/6,5-scale Tempest Mk. V (Ian Bailey)
I bought the drawings for Ian Bailey's Tempest in the early 90s and it's now finally time to start the project. The hardwares (cowl, canopy, wing fairings and static spinner) were bought when they still were made by Nexus, but today all of the items are made by Ian Bailey himself (Ian Bailey Scale Model Designs). I was lucky to inherit an aluminium and a static spinner and a canopy from Brian Borland's late Tempest. His model was almost in exact the same scale and was lost during the F4C World Championships in Switzerland in 2000.
I have been in contact with Ian Bailey and he gave me some good advice and tips to improve the model. My drawings were made 15 years ago..
When the model was designed the FAI weight limit was 5kg and IB used an OS 120FS in the prototype. His later models were fitted with Super Tigre 3000 (30ccm), weighed 7kg and flew much better!! The basic modification Ian made was to add full depth 3mm ply dihedral braces on the leading edge and main wing spar joints and also to the wing centre panel to spread the landing loads. These are not shown on my drawings but will be made. Ian actually test flew a Tempest built by a customer who had a Quadra 42 petrol fitted with an all up weight of 10kg. Ian said that it flew better than his at 7kg!!
The only complain about Ian Bailey's Tempest, when reading several Forums on the Internet, is the need for 2 lbs of lead in the nose. According to the drawings that is to say.
But Ian Bailey told me that on his models he has placed the RX, retract and on-board glow batteries on a metal plate above the engine and didn't have to add any nose weight to achieve the CG balance point. In fact, the planes were slightly nose heavy!! Ian said that the important issue is trying to keep the tail end light. On one model he actually used 1/32" (instead of 1/16") exclusively but didn't achieve any weight saving so most of the weight is not in the thickness of the balsa but in the covering and paint.
I did some comparisons with Artur Bentley's 1/48-scale drawings and I think the models did OK. The faulty spinner diameter is noted on the drawings as Ian Bailey used a larger commercial spinner on the prototype. The fin with dorsal fin and rudder which is to long will probably get right as I'm thinking of using Brian Taylor's fin. Enlarged to the correct size of course! The lenght of the fuselage is probably harder to correct.
This project started early 2004 and is at the moment (2014) still not finished, but just put "on hold" for other projects.
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