Surprise surprise

[Mars]

So much for a release to service.

In a recent post in the pictures thread, a comment was made on the advisability/requirement of an inspection following a landing in a field where the tail rotor was in the crops. For some reason it was deleted - the warning was well founded and should have remained.

Mars

NTSB Identification: ANC11TA110
Nonscheduled 14 CFR Public Use
Accident occurred Friday, September 23, 2011 in Seward, AK
Aircraft: BELL 206 B3, registration: N204PA
Injuries: 3 Uninjured.
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.

On September 23, 2011, about 1116 Alaska daylight time, a Bell 206 B3 helicopter, N204PA, sustained substantial damage when it collided with terrain while maneuvering at a low altitude, and encountered flat light conditions on the Harding Ice field, about 10 miles west of Seward, Alaska. The helicopter was being operated by Pathfinder Aviation, Homer, Alaska, as a visual flight rules (VFR) public use passenger flight, in conjunction with the National Park Service (NPS), under the provisions of 14 Code of Federal Regulations Part 135, when the accident occurred. The commercial pilot and the two passengers were not injured. Instrument meteorological conditions prevailed at the time of the accident, and company flight following procedures were in effect. The purpose of the flight was for NPS employees to sample and monitor the glacier's snow and ice field.

In a written statement provided to the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) dated September 24, a passenger in the helicopter at the time of the accident, reported that while traveling from one landing site on the Harding Ice field to another, visibility deteriorated rapidly, making it difficult to see the ground surface. The helicopter unexpectedly touched the surface of the ice field, and came to rest with the tail rotor in the snow. The helicopter was shut down, and another helicopter came to the site to remove the passengers.

According to a representative of the operator, an aviation mechanic came to the site, and examined the helicopter. Finding no damage, the helicopter was started, and brought to a hover. During the hover, a tail rotor driveshaft coupling separated, and the helicopter was set down on the ice field without further damage. Due to approaching weather, the helicopter was picked up by a larger helicopter, and returned to Homer.

[Gemini Twin]

You are quite right Mars. I remember the early Bell 47 T/R blades had soft aluminum strips secured to the tips, that would be deflected back if the blades touch anything but air. When found bent a serious inspection of the T/R system, including blade replacement if I remember correctly, was required.

[Saint Jack]

The post Mars is referring to is (was?) mine. I commented on seeing the photograph in Post #5282 on Page 265 of the 'Rotors Heads Around The World (inc. Views From The Cockpit)' thread.

I was simply pointing out that landing in a field of very tall crops that are capable of being struck by the rotating tail rotor requires a Sudden Stoppage Inspection to be performed as called out in the B206 MM.

So Moderator, why was this timely reminder, that has a direct bearing on safety of flight, deleted?

[Senior Pilot]

So Moderator, why was this timely reminder, that has a direct bearing on safety of flight, deleted?

The remark was deleted because it was not pertinent to our photos thread, Rotorheads Around the World.

What you may see as a 'timely reminder' (why? what was timely about it?) we see as an unnecessary dig at a pilot who goes to a lot of time and trouble to share with us his passion for flying in a particularly beautiful part of the world.

[Savoia]

I am supportive of the Moderator's actions. RATW is the single most viewed thread on the entire PPRuNe network and, as mentioned, is a photo thread.

The Moderator has permitted this technical/operational matter to be addressed on a seperate thread (here) as an alternative location for the comments which were posted.

I am also wholly supportive of promoting caution - always - but would say that with regard to the image in question none of us can know for certain what degree of risk was involved. I can show you a dozen helicopter-in-field photos, some of which deliver an initial reaction of 'alarm' but where no significant hazard existed.

I myself have set-down, on numerous occassions, amidst Elephant Grass in Africa where the tail rotor was placed over a bald patch or between a convenient channel in the grass and something similar may well have been the case in Nepal.

I am sure that Saint Jack's comments were offered in goodwill, doubtless wishing to highlight the potential risk - all the Moderator has done is to preserve the continuity and flow of PPRuNe's most successful picture thread and to allow the matter to be raised again in a more appropriate setting.

[arismount]

I like the pics from Nepal as well, but there are a lot of pre-accident links that are shown or talked about in them. That 206 shut down in the cornfield where the t/r is clearly shown surrounded by higher corn is one. Writing about landing with 6% fuel left in the tank is another. Yet another is using nasal cannula O2 at 23,000 feet, when the max altitude for effectiveness of a cannula system is 18,000. I don't know the guy, he takes good pictures, but the stuff he documents is pretty dangerous and when you keep pushing stuff that is pretty dangerous, something bad happens.

[Savoia]

I'm guessing that along with the tens of thousands of drivers who fly with smaller companies the world over, Vertical Freedom is most likely working with what he's got in terms of the oxygen kit and doing the best he can to make things happen as safely as posible in respect of pulling pax out of high altitude locations.

Hundreds of helicopter outfits the world over are isolated from the privileges of professionally regulated oversight, especially in developing nations, and in order to survive their drivers must simply do their best to make things work. Often its a case of choosing between the lesser of two evils. Historically, many countries (including North America and Europe) have been through this process.

However .. keep the comments coming, you never know, your concerns might just prick a pilot's conscience in the right way and result in averting a tragedy.

[Fareastdriver]

max altitude for effectiveness of a cannula system is 18,000

All very nice for people who have spent all their lives at sea level but born and bred several thousand feet up would most certainly prove otherwise.

[John Eacott]

Yet another is using nasal cannula O2 at 23,000 feet, when the max altitude for effectiveness of a cannula system is 18,000.

As a USA registered Rotorhead, I guess that you are quoting the FAA restriction of 18,000ft for cannula use. I suspect that Vertical Freedom is not operating under FAA regulations?

There are suppliers online who provide O2 Cannula systems for ops to 23,999ft. Google is quite clever at finding that sort of stuff ;)

[Saint Jack]

When I first entered this industry a long, long time ago, one of the first things I was taught was never to keep quiet if I spotted a potential hazard to flight safety. I have followed this practice throughout my career and when I have made such comments to other professionals, both pilots and mechanics, they have always been recieved in the spirit in which they were made.

The B206 sitting in the field with crops tall enough to intrude into the tail rotor disc area is a potential hazard to flight safety, i.e the potential to result in a tail rotor strike requiring a Sudden Stoppage Inspection before further flight.

My comment was NOT "...an unnecessary dig at a pilot..." it was intended to highlight circumstances which could have lead to yet another accident in an area that has a very high aviation accident rate, 'arismount' also saw indications of potential hazards. I considered my comment a 'timely reminder' simply because the last accident in Nepal, with 19 fatalities, is still being discussed in the 'Rumours & News' thread.

Nevertheless, I consider myself chastened and promise not to post in the wrong thread again.

[mickjoebill]

I think the thread is superb as it reminds us of what can be done.

However perhaps there is an issue is novice pilots and others who, seeing a picture of an aircraft in a particularly unusual/dramatic situation, will underestimate the degree of risk because there are nil negative comments about the photo from the wealth of expertise on tap at Pprune?

Perhaps there could be a reminder on the thread that negative comments are not encouraged and so viewers should make their own judgements on the legality or safety factors of the situation?


Mickjoebill

[Krishan]

I think we should freely make comments as long as it's in good faith. The risk is that someone who is sending us heart-warming pictures might feel discouraged. May be we can make the comments on another thread without linking to anyone. Long back, I had an accident which could have been avoided if had recieved a tip from an experienced pilot. But we did not have such easy communication facilities as we have now. How about someone starting a thread, "I learnt from that"

[Senior Pilot]

How about someone starting a thread, "I learnt from that"

Like this? I learned about flying from that (http://www.pprune.org/rotorheads/174184-i-learned-about-flying-ilafft.html) ;)

There is no need to get too carried away about what can be discussed in Rotorheads, nor where: most of us are wise enough to apply commonsense. The Mods will, however, keep threads on topic when thread drift is not acceptable or not needed. You all understood that when you signed up to PPRuNe, and it doesn't/shouldn't require a reminder until something like this thread develops.