Mike Meier <<Mike>> writes:

The T2C 144 HGMA certified values are 5 degrees inner and 7 degrees outer, with the rear keel at the rear wire junction at 0 degrees.

The T2C 154 manufacturer values (which will hopefully be HGMA certified values - the package is under review now) are 4 degrees inner and 6 degrees outer, with the rear keel at the rear wire junction at 0 degrees.

The five degrees inner and seven degrees outer on the T2C 144 corresponds to two turns down on each sprog from where we set them stock at the factory during production.

We vehicle tested the glider at the stock setting, and at four turns down from stock, and it passed the HGMA requirements at both settings, so we conclude that it also passes at two turns down. We flight tested the glider at the stock setting and at two turns down, and it passed the HGMA requirements at both settings. It is therefore certified at the two turns down from stock setting, (across the board, all sprogs).

At the stock setting, where we set them in production, and where we send them out, the angles measure 6.5 degrees inner and 8.75 degrees outer.

We've established the sprog angles for the regular (non C) T2's. Basically half a degree higher for the inners and one degree higher for the outers.

Mike agreed that two turns is approximately equal to between one and a half to one and three quarters degrees (as can be seen using the number given above).

An updated version of the T2 and T2C manual will include:

The VG should again be set at full tight. The minimum angles should be:

T2C 144 Outer Sprog: 7 degrees Inner Sprog: 5 degrees

T2C 154 Outer Sprog: 6 degrees Inner Sprog: 4 degrees

T2 144 Outer Sprog: 8 degrees Inner Sprog: 5.5 degrees

T2 154 Outer Sprog: 7 degrees Inner Sprog: 4.5 degrees

So when Wills Wing sends out T2C 144's to their customers the sprogs are set at 1.5 (inner) and 1.75 (outer) degrees higher than the certified values.

Regarding the measurements to be made at Laragne, Mike writes:

Anyway, with the two degree allowance, I would think you guys should be fine.

I guess this can be used to say that the manufacturer is saying that if we are within two degrees of the certified values (after all this is the margin of error) we will be okay, so my wording of the Certification Statement above would still be okay.