On Friday, September 7, 2018 at 9:08:28 AM UTC-4, Nick Kennedy wrote:
This has turned into a very interesting thread. It looks like we may be using some newer much better varios in the near future.
Another interesting aspect is Mike Borgelt describing the AOA change and the possible cause of low level, low speed [ in the pattern] accidents.
When were up high cruising at 80-100 knots we fly into 10 knots up all the time and pull hard to slow down and get ready to circle. Up high at speed this is no problem. Down low and slow at say 60 knots that 10 knot thermal you just hit may cause a major problem. I think we may be flying way to slow in the pattern. Looking at the stall/spin rates, in all parts of the arrival pattern, I might be right.
I like using the Knauff idea of having a longer higher final leg, and as my max flap extension speed in my LS3a is 86 knots, I try to keep it over 70 knots the whole way to the deck, works for me. This may sound fast and it is. I don't want to stall close to the ground by some rouge air or a booming thermal.
This fast in the pattern stuff was taught to me by Bob Faris CFIG
So far so good!

Regarding air speeds in the pattern, in a prior sequence the subject came up about the correct speed to fly 2-32s in the pattern. Some of the folks responded that 70 knots was way too fast. Yet this was the airspeed most of us using them in our commercial operations flew them at in New England starting in the late 60s. Despite the fact that the 2-32 had a reputation for spinning in, I don't remember any base to final turn spin ins in New England which suggests that the FBOs who came before me like Jim Doyle and John MaCone were doing something right.

What I do remember was a triple fatality involving a 2-32 in which the glider pilot did not properly lock the canopy prior to take off and stopped flying the glider instead of pulling the release on the ground roll the moment the canopy started flopping. He continued to attempt to close the canopy until the glider reached 100 feet at which point the tow pilot was forced to release the glider. A similar accident also occurred in New England in an ASK-21 that killed the passenger sitting in the front seat along with another 2-32 accident in which the glider pilot had a canopy locking failure on take off on Oahu that killed the pilot only. I suspect there were others I never heard about, after we switched hobby businesses. However we were not immune to a 2-32 spin, that can occur in many different situations. We had a low altitude 2-32 spin in at Plymouth MA, when a tow pilot who obviously was not awake early in the day attempted to tow a 2-32 at its stall speed of 50 mph after landing with the flaps down and neglecting to raise them for the next tow. The 2-32 pilot, unable to keep up with the tow plane, decided to do a 180 return instead of landing straight ahead causing the 2-32 to enter a spin low and hit a cross taxiway right wing down which collapsed and absorbed most of the impact energy injuring the ankles of the passenger only who was sitting in the front seat. The spin in discussions possibly caused by sharp edged vertical gusts are corroborate in YOs discussion in Soaring of the 1986 Regional at Sugarbush in which five gliders were damaged, one fatal, two of which occurred when folks attempted high speed finishes flying too slowly pulled up to go around and instead of gaining altitude spun in. The probable cause was a rotor that frequently forms right over the airport and which on a good wave day when John MaCone operated Sugarbush, broke most of his tow ropes forcing John to go out and purchase a spool of 1/4 inch Nylon rope.

While these comments are not 100% on topic, they highlight what I consider to be a significant problem in our society: disseminating safety information in a manner that does not draw attention to critical safety problems that frequently repeat. In addition, when you can go on the web and watch a video that shows a 1-34 pilot demonstrating precisely what not to do when a canopy flies open on the ground roll or just after lifting off, in which he demonstrates how to fly the glider using one hand to hold the canopy while the other flies the glider, we have a big time problem. Not only are we not reiterating safety issues that were discovered years ago along with their solutions (Schweitzer in response showed that all of their gliders could fly with the canopy flopping), but we are not making a fuss when someone comes along and demonstrates precisely what not to do! As YO also points out, in other countries, folks don't learn to do high speed passes on their own, which is what he claims was the cause of the two rotor induced spin ins at the Bush that did surprisingly did not injure either pilot.