TE Probe install?

I'd like to install a TE probe in the fin of my ASW 19.

What angle should the prob receiver be installed at on the fin?

It looks like most TE probes are installed so the probe is parallel to the horizontal stabilizer.

Is there an optimal spot on the fin to install the TE probe?

Thanks,

Nick

On Wednesday, February 18, 2015 at 4:16:57 PM UTC-5, wrote:
I'd like to install a TE probe in the fin of my ASW 19.

What angle should the prob receiver be installed at on the fin?

It looks like most TE probes are installed so the probe is parallel to the horizontal stabilizer.

Is there an optimal spot on the fin to install the TE probe?

Thanks,

Nick

Mount your probe as high as practical, about 4 inches down from the top of the fin, with the probe parallel with the center line of the tail boom.
Probe should be at least 24 inches long, preferably a bit more.
Good luck
UH

What UH said, plus....

The end of the probe should be turned UP!

Shields on!

Kirk
66

If there is no TN about this would I install the TP probe parallel to the datum line described for calculation of weight and balance. This is most likely the attitude you have in flight.

On Wednesday, February 18, 2015 at 4:16:57 PM UTC-5, wrote:
I'd like to install a TE probe in the fin of my ASW 19.

What angle should the prob receiver be installed at on the fin?

It looks like most TE probes are installed so the probe is parallel to the horizontal stabilizer.

Is there an optimal spot on the fin to install the TE probe?

Thanks,

Nick

ILEC has a service bulletin describing where they recommend the probe be mounted. I will paste info here for your reference.


"Fitting of the tube: On modern sailplanes, a short brass tube which serves as the receptacle for the probe is mounted on the aft fuselage or, more commonly on the vertical stabilizer. These mounts are available from the dealer.

Be sure the inner surface of the receptacle is smooth, as any roughness will damage the o-ring seal. Lightly grease the inner surface of the receptacle. (Vaseline works well.) The bore of the receptacle must be smooth and within +.02 -.00 mm tolerance.

Position of the tube: It is strongly advised not to position the tube in the vicinity of the wing, or even worse, in front of the canopy. Such positions should only be used on very low performance gliders with a narrow speed range when no other way is possible. If you must mount on the fuselage, try to mount it at least one meter behind the trailing edge of the wing.

The position high on the vertical stabilizer is best. The probe head should be in line with the top of the vertical stabilizer, or in the case of T tailed gliders, in line with the horizontal stabilizer. Positions half way up the vertical stabilizer are normally not as good because of the airflow interference with the fuselage, tailplane, fin and the wake of the wing and fuselage.

Alignment: You may closely approximate the best position by making the probe parallel with the axis of the aft fuselage cone. A more precise method is to determine the inclination of the glider in flight with the help of a spirit level, at the speed of best glide. Level the glider in this position, and adjust the tube to be level. For fuselage mounts, the base of the stem should be perpendicular with the fuselage.

Orientation: On the fin, position the tube so the measuring head is pointed upward. For the fuselage mount, the holes should be pointed aft."

The T/E line needs to be anchored inside the tail boom, away from the elevator push-rod and bell-crank. Slick way to accomplish this is to make up 2 anchor rings from 1" plastic pipe cut to 1" lengths. With the T/E line in place inside the tail boom, goop up the outside of the rings with epoxy and flox then slide them down the T/E tube placing (one, 1/3 way and the other 2/3 way down the tail boom). When anchors are located at the proper spot inside the tail boom, allow the T/E line to lower down so that the rings come to rest on the bottom of the boom. The epoxy and flox mix will slowly ooze down and stick to the inside of the fuselage. This is from Will Schuemann as a way to add aft statics for the 301 Libelle.
JJ