27 crash at Ely?

On Wednesday, July 22, 2020 at 9:09:19 PM UTC-7, Eric Greenwell wrote:
6PK wrote on 7/22/2020 3:29 PM:
"Hammering the rudder" is absurd and is asking for an inadvertent
spin which BTW I'm sure the cause many of lives lost near terrain.

My understanding is the advice applied to a glider that is flying
- not stalled - but not fast enough to generate roll greater than
the excess lift under one wing.
Full rudder would help the other wing develop more lift.

Not just rudder, but push forward on the stick as well. Stall speed decreases as G load decreases. When attempting to thermal and maneuver near the rocks, I always make sure that I can dive out of trouble - NEVER PULL! So if the glider starts getting squirrely or tossed around, I push, bank, and rudder to get away from the rocks. If full aileron and staying coordinated isn't enough, then slamming the rudder to help the roll works nicely. The glider shouldn't stall as I approach zero G, but if it does, the incipient spin and recovery is still helping me get away from the rocks.

Just as with aerobatics and other advanced maneuvers, don't do this without proper training and/or practice in a safe environment. And if you plan to use a tool such as this, make sure you've been practicing, so it's second nature. Diving at the ground and obstacles is something that has to be learned and counterintuitive for the novice.

In the flatlands east of the Colorado Front Range, I've experienced a downburst several times, and generally at 1000-1500' AGL near the airport. The glider starts to feel like it's falling and airspeed is dropping. I push the nose forward and even when in what seems like a 45 degree dive, I'm still barely above stall speed. The ground is coming up fast, but I don't dare to pull back. Eventually, airspeed builds, and I end up levelling off at less than 100' and 90-110 KIAS or more. Luckily this has only happened either directly over the runway, or on downwind, and I had enough energy to make a safe landing. But I was prepared to make a controlled crash in the direction I was headed. A similar technique applies when working a thermal below the ridge crest.

5Z

So many folks seem to be afraid of the rudder.Â* It's just another flight
control and, properly used as Tom says, can make the difference.Â* I use
lots of rudder routinely in the Stemme to get the nose down after a
sharp pull up in a thermal.Â* There's a lot of momentum in the Stemme due
to its weight at speed and it takes a steep pull to center a thermal
quickly.Â* Hard left rudder (since I'm on that side of the aircraft) gets
the nose slicing down towards the horizon.Â* Remove most of the rudder
and apply back stick to recover at or slightly below the horizon.

And BTW, I'll argue that there's no such thing as "stall speed", it's
always about angle of attack.Â* Unloading the aircraft reduces AoA,
keeping it below the critical angle.

On 7/22/2020 10:45 PM, 5Z wrote:
On Wednesday, July 22, 2020 at 9:09:19 PM UTC-7, Eric Greenwell wrote:
6PK wrote on 7/22/2020 3:29 PM:
"Hammering the rudder" is absurd and is asking for an inadvertent
spin which BTW I'm sure the cause many of lives lost near terrain.

My understanding is the advice applied to a glider that is flying
- not stalled - but not fast enough to generate roll greater than
the excess lift under one wing.
Full rudder would help the other wing develop more lift.
Not just rudder, but push forward on the stick as well. Stall speed decreases as G load decreases. When attempting to thermal and maneuver near the rocks, I always make sure that I can dive out of trouble - NEVER PULL! So if the glider starts getting squirrely or tossed around, I push, bank, and rudder to get away from the rocks. If full aileron and staying coordinated isn't enough, then slamming the rudder to help the roll works nicely. The glider shouldn't stall as I approach zero G, but if it does, the incipient spin and recovery is still helping me get away from the rocks.

Just as with aerobatics and other advanced maneuvers, don't do this without proper training and/or practice in a safe environment. And if you plan to use a tool such as this, make sure you've been practicing, so it's second nature. Diving at the ground and obstacles is something that has to be learned and counterintuitive for the novice.

In the flatlands east of the Colorado Front Range, I've experienced a downburst several times, and generally at 1000-1500' AGL near the airport. The glider starts to feel like it's falling and airspeed is dropping. I push the nose forward and even when in what seems like a 45 degree dive, I'm still barely above stall speed. The ground is coming up fast, but I don't dare to pull back. Eventually, airspeed builds, and I end up levelling off at less than 100' and 90-110 KIAS or more. Luckily this has only happened either directly over the runway, or on downwind, and I had enough energy to make a safe landing. But I was prepared to make a controlled crash in the direction I was headed. A similar technique applies when working a thermal below the ridge crest.

5Z

--
Dan, 5J

On Thursday, July 23, 2020 at 10:03:12 AM UTC+12, Eric Greenwell wrote:
6PK wrote on 7/22/2020 10:54 AM:
I share this opinion. BTW the main rules are; keep the speed up (so you won't run out of ailron) and stay coordinated.


"Keep the speed up" isn't a rule, it's just encouragement. How can a pilot
determine the flying speed is fast enough? I don't fly faster just because I'm
circling near the slope of a ridge, or mountain face; generally, I think I fly
fast enough to handle the turbulence easily. Coupled with that is moving farther
from the rocks the bumpier the air is. So far, that's worked, but I have no idea
how to put that fuzzy advice into something another pilot can use.

The 'rule' I use and teach is the take your target thermalling speed and add five knots for terrain and five knots for turbulence, plus half the wind speed. So a bumpy thermal in ten knots of wind would have me starting turning fifteen knots faster than normal. As you get the feel for the thermal you might pull those margins in.

Running onto a ridge I arrive with all my safety margins and only ease them back if I'm really confident that things are better than I thought. Like most pilots who fly along ridges on unstable days I have been rolled towards the hill a few times. Nothing outrageous, but it gets the heart rate up when your are holding the stick hard on the stop and still not rolling away. I do notice many pilots aren't really using full control movement. I tell them the reason we have control stops is to give you somewhere to rest your hand while you wait for a response.

Using the rudder is important, but you do not want to get uncoordinated. Full aileron is likely to want a matching amount of rudder though. This varies from glider to glider and with speed, so you need to know your aircraft.

And, I'm sure the speed and distance depends a lot on the type of glider, in
addition to pilot skill, but I can't even tell someone how far I am from the rocks
- no way to measure, so it's just guessing if I mention a number, and the other
pilot is just guessing, too, when he tries to stay that far away.

Judging clearance is a skill that can take a while to learn. Some mountains lack features that indicate scale. Mountains with trees, roads, vehicles etc offer scale that people are used to. Bare rocks don't.

Best to be close enough to be in the lift, but not closer. I only rock polish on weak predictable days where you ned to be close to get lift. Gentle ridge lift or weak anabatic flows. If it's unstable you need a lot more room to allow for those thermals that might roll you into the hill. In thermic conditions I'd allow almost a full turn of space, maybe 150 - 300 meters. That's horizontal clearance. For vertical clearance you need to consider the slope and escape routes. Being close to steep slopes is generally safer than shallow slopes because your escape routes get more clearance sooner.

Maybe I'm just lucky, because I've never experienced the loss of roll control for
more than, say, 20 degrees. Or maybe I scare easily enough, that I've always given
myself enough airspeed and distance. How do I tell the difference between luck and
good piloting?

It's good piloting if you don't crash and bad luck if you do?

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

--
Phil Plane
Omarama

On Friday, July 24, 2020 at 10:15:32 PM UTC+1, wrote:

Snip:
" Judging clearance is a skill that can take a while to learn. Some mountains lack features that indicate scale. Mountains with trees, roads, vehicles etc offer scale that people are used to. Bare rocks don't.

Phil Plane
Omarama

A geometrical observation about judging distance from a mountain slope:

If you travel at 60 knots ground speed in a straight line along a mountain slope (or past any point or mast etc) then for every second that it takes for a chosen reference point to pass from 45 degrees ahead to directly opposite then you (not the wing tip) are 100 feet from the reference point. At 90 knots it would be 150 feet and so on. This applies in any plane so it works for crossing over ridges as well.

Obviously you can't judge this exactly but it is surprisingly easy to get in the ball park and I am sure it is the relative rate of motion that experienced mountain pilots intuitively use. I figured it out during my first trip to the Pyrenees after I thought I was flying close to a steep featureless rocky ridge and was overtaken on the inside by a rather small looking Duo Discus. I realised that I needed a way to calibrate my inexperienced judgement where there were no size reference features.

John Galloway

"Being close to steep slopes is generally safer than shallow slopes because your escape routes get more clearance sooner."

I wonder how steep the terrain was? The Whites can produce brutal air currents. It;s like the blink of an eye and you. Scares you enough to leave some some extra escape room on those days. Terrain is a very complex thing. It seems ( I am speculating here) that the terrain where the accident occurred was not very steep.

Can someone confirm?

On Saturday, July 25, 2020 at 12:18:19 PM UTC-7, wrote:
"Being close to steep slopes is generally safer than shallow slopes because your escape routes get more clearance sooner."

I wonder how steep the terrain was? The Whites can produce brutal air currents. It;s like the blink of an eye and you. Scares you enough to leave some some extra escape room on those days. Terrain is a very complex thing. It seems ( I am speculating here) that the terrain where the accident occurred was not very steep.

Can someone confirm?

The slope is medium in that it isn't vertical. In places it is very steep, as near vertical.

After giving it some thought, I think that Marak was thermalling up the slope in a left turn, below the ridge top, when he saw his opportunity to clear the ridge and circle directly over it in the strongest lift. I have done this many times, but this time he got a gust that stalled the low (left) wing and he dropped. He almost would have cleared the ridge, but did not. End of story.

Tom

On Saturday, July 25, 2020 at 12:18:19 PM UTC-7, wrote:
"Being close to steep slopes is generally safer than shallow slopes because your escape routes get more clearance sooner."

I wonder how steep the terrain was? The Whites can produce brutal air currents. It;s like the blink of an eye and you. Scares you enough to leave some some extra escape room on those days. Terrain is a very complex thing. It seems ( I am speculating here) that the terrain where the accident occurred was not very steep.

Can someone confirm?

The slope is medium in that it isn't vertical. In places it is very steep, as near vertical.

After giving it some thought, I think that Marak was thermalling up the slope in a left turn, below the ridge top, when he saw his opportunity to clear the ridge and circle directly over it in the strongest lift. I have done this many times, but this time he got a gust that stalled the low (left) wing and he dropped. He almost would have cleared the ridge, but did not. End of story.

Tom

On Saturday, July 25, 2020 at 9:56:26 PM UTC-7, 2G wrote:
On Saturday, July 25, 2020 at 12:18:19 PM UTC-7, wrote:
"Being close to steep slopes is generally safer than shallow slopes because your escape routes get more clearance sooner."

I wonder how steep the terrain was? The Whites can produce brutal air currents. It;s like the blink of an eye and you. Scares you enough to leave some some extra escape room on those days. Terrain is a very complex thing. It seems ( I am speculating here) that the terrain where the accident occurred was not very steep.

Can someone confirm?
The slope is medium in that it isn't vertical. In places it is very steep, as near vertical.

After giving it some thought, I think that Marak was thermalling up the slope in a left turn, below the ridge top, when he saw his opportunity to clear the ridge and circle directly over it in the strongest lift. I have done this many times, but this time he got a gust that stalled the low (left) wing and he dropped. He almost would have cleared the ridge, but did not. End of story.

Tom
My son is backpacking the Sierras right now and just reported, “winds were crazy all night, huge gusts then, just stop at 8700’ ridge top�.............this got me remembering hiking up Siegel Mountain, near Minden to place a marker where Jack Bamberg crashed for unknown reasons. About noon it was dead calm, then the wind would come up a good 15 knots, then suddenly stop. Fifteen minutes later it would do it again. The winds were up slope and probably thermals. Next day we placed another marker on the White Mountains just east of Bishop at about noon. Very gentle up slope wind. One of the guys brought along a roll of toilet paper and threw up a handful of single sheets at the edge of the little plateau where Tom Madigan crashed. The paper rose up in the gentle up slope winds and then curled over and came back down to the sagebrush!................we never really know what’s going on just outside our little cockpit!
JJ

On Saturday, August 22, 2020 at 8:45:10 AM UTC-7, John Sinclair wrote:
On Saturday, July 25, 2020 at 9:56:26 PM UTC-7, 2G wrote:
On Saturday, July 25, 2020 at 12:18:19 PM UTC-7, wrote:
"Being close to steep slopes is generally safer than shallow slopes because your escape routes get more clearance sooner."

I wonder how steep the terrain was? The Whites can produce brutal air currents. It;s like the blink of an eye and you. Scares you enough to leave some some extra escape room on those days. Terrain is a very complex thing. It seems ( I am speculating here) that the terrain where the accident occurred was not very steep.

Can someone confirm?
The slope is medium in that it isn't vertical. In places it is very steep, as near vertical.

After giving it some thought, I think that Marak was thermalling up the slope in a left turn, below the ridge top, when he saw his opportunity to clear the ridge and circle directly over it in the strongest lift. I have done this many times, but this time he got a gust that stalled the low (left) wing and he dropped. He almost would have cleared the ridge, but did not. End of story.

Tom
My son is backpacking the Sierras right now and just reported, “winds were crazy all night, huge gusts then, just stop at 8700’ ridge top�.............this got me remembering hiking up Siegel Mountain, near Minden to place a marker where Jack Bamberg crashed for unknown reasons. About noon it was dead calm, then the wind would come up a good 15 knots, then suddenly stop. Fifteen minutes later it would do it again. The winds were up slope and probably thermals. Next day we placed another marker on the White Mountains just east of Bishop at about noon. Very gentle up slope wind. One of the guys brought along a roll of toilet paper and threw up a handful of single sheets at the edge of the little plateau where Tom Madigan crashed. The paper rose up in the gentle up slope winds and then curled over and came back down to the sagebrush!................we never really know what’s going on just outside our little cockpit!
JJ

There was another crash at Ely a few years ago under similar gusty wind conditions. The pilot lost control of the glider and successfully bailed out. Mountains seem to amplify the magnitude of the gusts. Staying on the ground during on these days is clearly prudent. I have said before, I would rather be down here (on the ground) wishing I were up there (flying), than be up there wishing I was down here.

Tom