Emergency Procedures

[Blackmac]

L3Driver:

 

It is rather obvious that you are in camp with nothing else to do than dream up loaded questions.

 

It is not an easy question to answer, it is all predicated on the circumstances and how well you react.

 

We will talk single burner for now:

 

You will notice a vertical hump (decrease in rotor rpm) low rotor rpm horn (if working), then an engine "out" horn, followed by all warning lights coming on and an increased tightening of the sphincter muscle. This will all happen before you even look at the N1 Gage.

 

Twin burner: After engine out light comes "on", reduce airspeed to accommodate increased power settings on remaining engine and if at "max gross"(B212) proceed to the scene of the mis-hap.

 

Have fun, I made it three (3) times.

 

Cheers, Don

 

PS: As I said there are many versions to this story and all believable.

[Over-Talk]

L3, you are on the right track as far as wanting to get the pole down....but sometimes you are in a point-of-flight where keeping the collective up for just another second may be a life-saver.

 

As you spend more time in this business you will hear stories about guys that crash-landed ships because of 'over-reacting' to a N1 transducer/gauge failure.

 

I immediately look at the torque gauge when I hear the horn.......if the engine quits, the torque guage will plummet instantly.

 

You will also get a pronounced yaw, unless you are in a very low power descent.

The TOT and RRPM gauges will be slower to fall, so they aren't a good indicator.

 

If you lower the collective and then cross-check, all the guages (and yaw) will be giving different (and confusing) signals.

 

Note that the horn and light that you get from a N1 gauge going below it's parameter (for whatever reason) is an engine-out horn....not a low-rotor horn. You probably have a second to act accordingly.

There may also be a failure of the NR transducer causing a low-rotor horn.

If you hear the low rotor horn you probably only have about half a second to react!!

 

If I hear any horn, my eyes head to the torque gauge while my hand gets a firm grip on top of the collective.

The old adage about "the first thing to do during an emergency is to fly the aircraft" is very appropriate here. The collective should only be lowered when the pilot has determined it is necessary, not just because a is horn beeping.

 

Two other related thoughts.......

1). Procedures by multi pilots are different......simply because of the redundancies built into a twin. The need for an immediate radical response to an emergency is very rare in a carefully designed multi.

2). A-stars have the same horn for the low rotor warning and for a hydraulic failure. I have seen many drivers react inappropriately during hydraulics training. Because they know what failure is coming (hydraulics), they don't remember to do a proper scan to determine if the collective should be lowered in reaction to a low rotor warning.

 

[helicopterjim]

Rotor RPM is life!

[twinstar_ca]

I picked up a copy of "Fatal Traps for Helicopter Pilots" yesterday when I was in YYC. Might be something you wanna pick up or order for when you are sitting in camp!! :up:

[AH1]

L3Driver:

 

It is rather obvious that you are in camp with nothing else to do than dream up loaded questions.

 

It is not an easy question to answer, it is all predicated on the circumstances and how well you react.

 

We will talk single burner for now:

 

You will notice a vertical hump (decrease in rotor rpm) low rotor rpm horn (if working), then an engine "out" horn, followed by all warning lights coming on and an increased tightening of the sphincter muscle. This will all happen before you even look at the N1 Gage.

 

Twin burner: After engine out light comes "on", reduce airspeed to accommodate increased power settings on remaining engine and if at "max gross"(B212) proceed to the scene of the mis-hap.

 

Have fun, I made it three (3) times.

 

Cheers, Don

 

PS: As I said there are many versions to this story and all believable.

 

 

 

There are no STUPID QUESTIONS, when someone asks, its because they don't know, and because everyone natters on about mentoring, the last thing you want to do is stop them from asking because they feel they'll be looked dowm upon.

[dammyneckhurts]

I'm in "camp" on a three and one and in the evenings we sit and chat or send e mails etc.. A few days ago i was reading an old thread about false N1 failures/indications and someone (a high hour, multi-engine,IFR, Instructor type) said that the only gauge you had to look at was the dual tach and that you didn't have to drop the pole. In my three years as a pilot i heard of two such failures. I thought that you get the collective down while looking at the gauges to determine if the stove is still on. Thoughts anyone?......... Thanks, L3driver

 

 

About 6 years ago I had such a failure in a 205, was in level cruise about 1000' agl with only 4 pax and all of a sudden the engine out starts blarin and flashin but it was very apparent that the engine was still running just fine. I say this because everything under my butt felt perfectly normal. Collective stayed up and I looked for a decent place to land and landed as soon as was comfortably possible so I could investigate things.

 

In contrast to this another time when I did have an actual engine failure of sorts, (was a fuel control partial decel issue just after takeoff fully loaded at about 200 feet and 45kts) the aircraft immediately felt like it was about to stop flying. The nose yawed, I could hear the RPM decay never mind the horn blaring, and I immediately lowered the pole, it wasn’t even a conscious decision it just happened.

 

My point here is that in an actual engine failure there is a lot more indications than just horns and lights. Next time you do a practice auto think about this....how does the machine feel when the throttle is rolled off, especially if someone else rolls it off and you have to correct for the big yaw and rapidly reducing rpm. We sort of get a false sense of what a real engine failure would be like because in many training environments the student handles the rolling of the throttle with lowering collective and adjusting peddles so it all feel "smooth and coordinated" Makes for a great coordination exercise for the student but sort of detracts from learning how an aircraft actually reacts to an engine failure.

 

I was fairly fortunate in that both of the above scenarios the aircraft was in a "steady state" i.e...I was not in the middle of a significant power change, turning, etc. so it was easy to tell what happening regardless of horns and lights. There are so many variables as to how one would react depending on the situation, on short final with a long line, head out the window etc....things happen pretty dam quick. Number one for me is "fly the aircraft" does it feel and sound like it’s still running? If so then keep going, take a few seconds to evaluate things, if the nose yaws big time for no reason then you defiantly have a problem regardless of what the light and horns may or may not be telling you.

 

DMNH

 

 

[Freefall]

Good reading thanks neckhurts

[rotorheadrob]

Every time something unusual happens my eyes go direct to rpm. The Rotor runs my pacemaker! That being said, if the nose stayed strait the stove is still on.

 

Signs of an engine failure: Nose goes hard left (or right in an A-Star), oil pressure drops, N1 Drops, N2 drops, TOT drops, engine goes quiet, horn goes off, and rotor RPM drops until you lower the collective.

 

As the dude with the sore neck said, you can feel it.

 

 

rob

[skullcap]

These are all great replies, but the time when something like an N1 tach generator causing huge panick attacks is usually(key word is usually) not in powered on flight straight and level, as if the aircraft is flying it will probably remain so. The time you have to be alert and aware is in a descent(logging, seismic, birdtowing,,,,well pretty much all jobs entail some sort of long descent at times.

 

So in your descent your engine monitoring alarm system fails,,,,N1 tach genny in jetranger for example, how do you determine that in fact is a false alarm QUICKLY? The power is down so is doubtful there will be much if any yaw if is a real failure. Everyone has their own procedure I guess, but I prefer N2/NTL for this, by checking this you will be also checking the Nr as it usually shares the same space. If your N2/NTL is ok and NR is ok then you are probably ok. But if the N2 is decreasing along with Nr with collective input get on with the procedure of maintaining Nr/autorotating/gov failure etc.

 

 

To my knowledge there is no light helicopter with a warning system utilizing N2/NTl rpm thus a false warning horn or light should not be present although, I feel that aircraft without N2/NTL indicating system such as B and BA's are severly lacking.

 

Rotor rpm is life but the heart of life is a living breathing turbine(N2).

 

 

p

 

 

[Ryan]

I had an N1 gauge fail on me a few years ago in an S76. Just cruising along and noticed the needle starting to twitch on one of the engines. No other indications to show it was anything other than the gauge, but we briefed an engine failure just in case.

 

The needle starts bouncing wildly and the engine out tone and lights start coming and going with the swings of the needle. Still no secondary indications that it's anything but the gauge and luckily we're directly over YVR so we land and swap out the gauge, problem solved.