wrote on 3/8/2021 1:33 PM:
Hello fellow glider pilots,
I have a question for the community, curious to hear people's thoughts. During my wave flight at KIYK in December, I experienced freezing of the controls (1996 DG303.) I suspect this is likely due to the low temperatures (-70F at 36K ft). I contacted DG and they had no information to share. Two possible causes could be thermal contraction issues or frozen grease. After looking over the ship with my A&P, it does not look feasible to regrease the mechanical circuit since almost all of the circuit is inaccessible (without cutting into the glass.) If it was thermal contraction, not sure what we could do to address this; this would also entail cutting into the glass.
So I am thinking about putting together a glider which could be used for this kind of flying and have been thinking about a SGS 1-34. A number of the older pilots out of KIYK have flown the Sierra wave in this model; the Boulder club used this model for its high altitude flying.
I am curious what you folks think of this plan? Is there a better ship to consider? Metrics I think are important to consider: known behavior at high altitudes, room for oxygen equipment, ease of access of mechanical control circuits, robustness (forces in rotor can be large), cost of glider, cost to maintain.
Given what I have read, the 1-34 seems to satisfy these criteria with the added benefit that it could be left assembled at the airfield. Terminal velocity dive brakes are an advantage for the 1-34.
Is there anything I am missing? Thanks in advance for your thoughts.
Keith
N303DG
I'm surprised the big problem is the glider controls at -70F. How did the pilot avoid freezing
at those temperatures?
I'm assuming you'd keep the DG303 for thermal soaring. What are your wave flying goals? If it's
altitude, the performance of the 1-34 is likely adequate; if it's distance, it's likely not
adequate, and you'd be better off staying lower in better performing glider.
--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1