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-   -   Colombia B206 crash 20.dec.21 (https://www.pprune.org/rotorheads/644348-colombia-b206-crash-20-dec-21-a.html)

Uplinker 26th Dec 2021 08:49

Just wondering how they will recover this helicopter?

Repair it on site or bodily move it to be repaired ? Either way, a very tricky job I suspect.

RVDT 26th Dec 2021 15:24

Apparently it was at about a bit more than 10,000 odd feet and it was not the first flight of that aircraft up to that spot. Not saying it was the same operator at the helm though.

Watching the video the aircraft is still OGE when it tops out on N1. Maybe it did just have IGE performance. At that altitude in a Jet Banger you would need all your ducks in a row.

Looking at a bit of historic METAR data from nearby it could have been as bad as ISA +20?

Another trap when operating at those altitudes is that you need to check that max N1 is available with a "topping check". Not everybody does them to see and it can certainly rip your nightie.

Most FCU's are slightly out and a missing .5% will end your day thanks to the exponential curve.

2°41'55.97"N 76°52'18.59"W if you are interested. There seems to be a road or track of some sort up there.

At least they walked away - luck.

havick 26th Dec 2021 16:23


Originally Posted by Uplinker (Post 11160956)
Just wondering how they will recover this helicopter?

Repair it on site or bodily move it to be repaired ? Either way, a very tricky job I suspect.

Probably external load it out on a Mi8 or similar metal.

haihio 26th Dec 2021 17:16

I’ve landed 206 B3’s at up to 12500 in ISA + 15 and the limit was always ToT not N1.
I could manage 1 pax at 12.5k and 2 at approximately 11k.
I can’t remember what Tq numbers I was getting but generally not close to maximum.

gulliBell 27th Dec 2021 03:48

That should be a "bread and butter" approach for any commercial B206 pilot. He had a bit of useful height and maybe a bit of useful airspeed when the rotor was heard to droop. His mistake is obvious. As soon as you hear the rotor start to droop the corrective action should be instinctive, and that does not mean you droop the rotor further in any attempt to land. The pilot needlessly pranged a serviceable helicopter through improper technique, and improper recovery action.

gulliBell 27th Dec 2021 03:52


Originally Posted by haihio (Post 11161110)
I’ve landed 206 B3’s at up to 12500 in ISA + 15 and the limit was always ToT not N1.

Agreed. In a 206B3 with an engine producing on-spec power you should be TQ limited up to about 8,000 ISA+15, and TOT or N1 limited above that.

gulliBell 27th Dec 2021 04:00


Originally Posted by Uplinker (Post 11160956)
Just wondering how they will recover this helicopter?

Repair it on site or bodily move it to be repaired ?.

That repair will need a jig so it can't be done in-situ, it's too badly banged up. I suspect the recovery/repair cost is likely to be significantly more than what the helicopter is worth, so not economic to repair. Push it over the side or cut it up into smaller pieces and sling it off the mountain bit by bit. Anyway, it's for the insurer to deal with now.

Bell_ringer 27th Dec 2021 06:26


Originally Posted by gulliBell (Post 11161233)
That repair will need a jig so it can't be done in-situ, it's too badly banged up. I suspect the recovery/repair cost is likely to be significantly more than what the helicopter is worth, so not economic to repair. Push it over the side or cut it up into smaller pieces and sling it off the mountain bit by bit. Anyway, it's for the insurer to deal with now.

Nah, plenty to salvage and sell.
That's potential FrankenRanger material right there :}

Hot and Hi 27th Dec 2021 09:03


Originally Posted by gulliBell (Post 11161232)
Agreed. In a 206B3 with an engine producing on-spec power you should be TQ limited up to about 8,000 ISA+15, and TOT or N1 limited above that.

So that means the pilot would have overtorqued and overtemped her anyway, before experiencing RRPM drop and losing tail rotor effectiveness?

Bell_ringer 27th Dec 2021 09:19


Originally Posted by Hot and Hi (Post 11161279)
So that means the pilot would have overtorqued and overtemped her anyway, before experiencing RRPM drop and losing tail rotor effectiveness?

Definitely overtemped. I wonder how many times the little red light has had to be reset, or maybe it had just burned itself out from overuse.

212man 29th Dec 2021 15:48


Originally Posted by Hot and Hi (Post 11161279)
So that means the pilot would have overtorqued and overtemped her anyway, before experiencing RRPM drop and losing tail rotor effectiveness?

Not overtorqued if N1 or TOT limited - by definition. If N1 limited then no overtemp either, but BellRinger seems to suggest that it would have been TOT limited at that DA, so yes it would have overtemped in that case.

gulliBell 30th Dec 2021 12:28

The C20/28/30 engine FCU will keep squirting more and more fuel into the engine until it arrives at N1 topping. So if you get to a TOT limit before the N1 limit, and keep demanding more power until N1 topping (when you can get no more power), you can seriously toast the engine. I've had a 206B3 at 11 grand ISA+15 but I can't recall which limit you will get to first, but it certainly won't be a torque limit. I always have my eyes shut whenever VFR above about 3 grand because it's not a place I like being. Over-torque a 206 engine and you aren't so much harming the engine, but the powertrain 'ant gonna like it and the AOG inspection might get real expensive to fix. I've got a hunch that cooking an engine without an over-torque might not be as expensive as the damage is confined to the engine hot section. All academic here as the accident aircraft is probably not economic to fix and is destined for the scrap heap, or the miracle room at the FrankenRanger factory.

Salusa 31st Dec 2021 03:47


Originally Posted by havick (Post 11161095)
Probably external load it out on a Mi8 or similar metal.

Mi-8 bit overkill.

​​​A Bell 212 would manage it. We lifted out a Longranger recently with a Bell 212 Eagle from a greater altitude than that. Blades, Hub and Mast off, dump any extra weight (battery etc).

Still value in the hull. Probably BER for rebuild but value in spares. Someone will likely buy it after the loss adjuster puts it out for bids.

havick 31st Dec 2021 10:06


Originally Posted by Salusa (Post 11162875)
Mi-8 bit overkill.

​​​A Bell 212 would manage it. We lifted out a Longranger recently with a Bell 212 Eagle from a greater altitude than that. Blades, Hub and Mast off, dump any extra weight (battery etc).

Still value in the hull. Probably BER for rebuild but value in spares. Someone will likely buy it after the loss adjuster puts it out for bids.

maybe overkill, but still cheaper given what’s available in the region. And you could lift it without removing anything.

Roundhill150 1st Jan 2022 06:08

Gullible, For someone who seems to be an expert on turbine engine management and operations at high altitudes seems odd that you are ****ting yourself at just 3000 feet.

gulliBell 1st Jan 2022 06:29


Originally Posted by Roundhill150 (Post 11163366)
Gullible, For someone who seems to be an expert on turbine engine management and operations at high altitudes seems odd that you are ****ting yourself at just 3000 feet.

Yeah, I get the heebie jeebie's and out of my comfort zone when I can see the ground far below me. Makes me want to find a cloud to hide in.

[email protected] 1st Jan 2022 09:30

Not an unusual condition for pilots Gullibell - plenty of threads over the years on pprune about it.

I don't normally have a problem when enclosed in an aircraft - although I hate heights like ladders and cliffs - but I flew a Gazelle with the doors off at only 1000' agl and felt distinctly uncomfortable in turns when I was looking straight down at the ground.

megan 1st Jan 2022 14:15

Found a number of chaps who were nervous flying at altitude, anything over 1,500', possible transmission failure being the cause. Had to be told 1,500 is OK for small arms but 50 cal goes a lot higher then that. Took one lad to 16,000 to show him the scenery.

[email protected] 1st Jan 2022 16:29

The main concern for many was uncontained fire at altitude, especially when gearboxes had a high proportion of magnesium in them.

megan 2nd Jan 2022 03:54

Not heard of that one prior crab, if you were of neurotic bent there is plenty to worry about, chap had vibrations (F-28) so went into power on auto to get to the ground as quick as possible, flared, nice landing, during the cool down the passenger said "Looks like someone has been here before us", pointing to a tail rotor in the bushes. Pilot climbed out to find the end of the tail boom had been chopped off, but couldn't see how it could possibly have happened. Turned out the forward bolts on the transmission had sheared and when pulling power to terminate the transmission rotated rear wards so chopping the boom, on lowering collective transmission fell back into place. Manufacturing fault in machining the bolt holes placing stress on one side of the bolt heads.

Always had thoughts of one of my instructors and Groomsmen, Jerry Hardy ex RN, who died in a Bristow 76 at Aberdeen when it threw a blade. Doesn't take altitude to kill you. Jerry on right doing the mail run for the HMY Britannia when the ship visited Oz 1970.


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