Altair 400 (oz14343)

About this Plan

Altair 400. Radio control sport aerobatic model, for electric power with Speed 400 motor. Wingspan 37.25 in, wing area 252 sq in.

Direct submission to Outerzone.

Quote: "Altair 400. Having enjoyed the Altair (oz14339), I scaled it down for a Speed 400 geared (hence the name) and 500 AR nicad/1100 NiMH cells. Then, when brushless outrunners became available, I replaced the S400g with a Skatty (1050 Kv) outrunner….and when Lipos became available, I replaced the round cells with Lipos of the same weight (gotta keep that CG!).

As you can imagine from all those modifications, the Altair 400 was around for many years – and flown a LOT during that time. Very stable (even in windy weather), the model was fully aerobatic – in fact, it met its end in a hangar accident, not flying!

I built the model in one piece, with access to all the innards via a pair on hatches in the fuse top. A nylon LG/UC strap, cut into an 'S' shape with a pivot screw at the center, engaged two toothpics to latch the hatches.

Covering was Doculam, trimmed with craft-store tissue held on with Aerogloss clear dope. I’m including un-trimmed pictures of the model as they will likely help in explaining how some bits were done. One quirk of mine is that I liked using ‘facing strips’, i.e., thin strips of balsa overlaying the side framework and keeping the covering from sticking to the verticals and diagonals.

The main LG/UC is sewn to the wing LE bulkhead bottom with braided fishing line (NOT monofilament!) tied off and soaked with thin CA. The three 9 gram servos sit line abreast, with the aileron servo in the center, driving the ailerons via torque rods).

Please remember that I built this model in 2006, but am writing this in early 2023, so I may not recall all the details. I obviously did like the layout, as I’ve used it over and over in high, shoulder, and low-winged forms!"

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