Primarily for general aviation discussion, but other aviation topics are also welcome.
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By T67M
#1810364
I need something a lot stronger! Let me think - no gyro instruments, no radio, no transponder, no idea of the cloudbase above terrain, apparently no idea of the terrain elevation, but still no problem legally.... But don't you dare try that if you have an engine.
#1810368
T67M wrote:I need something a lot stronger! Let me think - no gyro instruments, no radio, no transponder, no idea of the cloudbase above terrain, apparently no idea of the terrain elevation, but still no problem legally.... But don't you dare try that if you have an engine.


And who was PIC? They need to work on their handover of control
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By akg1486
#1810371
T67M wrote:I need something a lot stronger! Let me think - no gyro instruments, no radio, no transponder, no idea of the cloudbase above terrain, apparently no idea of the terrain elevation, but still no problem legally.... But don't you dare try that if you have an engine.

But they did have a piece of red yarn taped to the windshield.

I don't know anything about legal minimums for gliders, but the cloudbase in the video was definitely in the danger zone.
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By xtophe
#1810381
TheKentishFledgling wrote:Blimey...looks like the G-meter hits 8 G. Would that kind of glider be approved to that level? I've no idea.

Depending the mass and the wing tip configuration, they were either in the utility or aerobatic category.
So respectively 5.3g at Va and 4.0g at Vne
And 7.0g at Va and 7.0g at Vne

Speeds a bit odd during the big pull as it increases, there is a point they are above Va while at 8g.
<edit> not so strange if it is a spiral dive</>

So thanks to the 1.5 safety factor between limit and ultimate.
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By ls8pilot
#1810385
T67M wrote:I need something a lot stronger! Let me think - no gyro instruments, no radio, no transponder, no idea of the cloudbase above terrain, apparently no idea of the terrain elevation, but still no problem legally.... But don't you dare try that if you have an engine.


Actually they broke quite a lot of rules, flying IMC in NZ (where it is from) requires rating, instrumentation and clearance. In UK you need instruments and if you fly on an LAPL(S) or SPL - which you will need next year - you need a cloud flying rating. In class G as you know no clearance is needed. Doing this in UK you would be in trouble with the CAA and your club, so it's definitely not "no problem".

In NZ IMC for gliders is slightly different in its definitions from UK, however rules do not stop people making errors - as shown here. There was good commentary on all the errors by a NZ gliding instructor which has been removed from YouTube - presumably as this is subject to official investigation.

Watching it made me feel very ill, as a glider pilot with some ridge experience you can see the situation developing quite clearly and there were a number of opportunities to rescue the situation . Presumably a court case or official investigation will find out the exact facts. Basically at about 1:30 they should have turned right into clear air on the upwind side of the ridge away from the orographic, and done a "beat" back in the lift gaining height in clear air. Instead were lured into drifting downwind of the ridge (not enough lay-off into wind on their track), then resultant heavy sink taking them down into cloud with all the problems.

Shows the dangers of orographic cloud which can build very quickly in the right(wrong) conditions. AFAIK they recovered on the downwind side of the ridge and landed in a field undamaged - at least till the NZ CAA , their CFI and the other club members get hold of them!
By UV
#1810474
If you are going to soar a ridge that has any cloud on or near it you must treat that cloud as part of the hill....in other words avoid it at all costs.

As said above why did they turn left when it was clear the other way... it was downwind with the inevitable result.

Some interesting observations about the rate of descent. From 4000 ft down to the lowest point of 3450 ft the average ROD was 1833 feet per minute (or about 18 knots in gliding terms). In the last 10 seconds it had increased to nearly 2000 fpm.

The electric variometer at 3. 00, and before, seems to have gone past its stops and reads in reverse. Sometimes steadily. No stops?

As mentioned before the ASI increases during the “big pull” . Also unusual the Instantaneous G meter needle at the pull reads full Negative G., and is still reading negative G as the camera flips down. Hmmm....so wouldn’t it have needed positive G for that to happen?

Must have been some sort of strange attitude they were in. Were they inverted, or partially so?

Finally, I wonder whether they hit the ground at 3.06? Several things make me think so:
1. The camera is flipped own at 3.04 whilst the G Meter indicated negative G suggesting a sudden deceleration and
2. It goes from being really bumpy to suddenly very smooth.
3. Difficult to tell, but we’re there sounds of impact?
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#1810486
If that is a composite glider, there is an extra safety factor, which depending upon how the manufacturer handled certification was in the range 1.2 to 1.5.

So with a 5.3 limit load at Va, the failure point shouldn't have been less than 9.5g. A fact that almost certainly saved their lives.

But it has been far enough beyond limit loads, that I would hope the aircraft will be grounded and referred to the manufacturer for inspection requirements.

G