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-   -   Helicopter Ground-Runs Performed by Engineers/Mechanics (https://www.pprune.org/rotorheads/478698-helicopter-ground-runs-performed-engineers-mechanics.html)

Saint Jack 1st Mar 2012 03:22

Helicopter Ground-Runs Performed by Engineers/Mechanics
 
The recent AS350 accident in Brazil where the helicopter was destroyed on the ground by severe vibrations after landing brings to mind the perennial question of helicopter engine ground-runs being performed by engineers/mechanics. I had expected the thread on this accident to drift into this topic, but it seems to have faded away first.

When the question is asked, the most common and instant reply is "it isn't allowed", but when you ask for the authority of this reply you usually get a deafening slience or "we never do it". The next most common reply is "what if you get into ground resonance, you can't take-off to correct it".

Let's clear up the first reply, "it isn't allowed". Generally, only two parties can say this with total authority; a) the helicopter owner and, b) the helicopter insurerer, both for quite obvious reasons.

I only know of one country where legislation specifcally requires helicopter engine ground-runs to be performed by an approriately rated pilot.

In my previous company, nominated senior engineers/mechanics were trained and authorised to perform engine ground-runs, with limitations of course (no raising the collective etc.) and this was a boon to the end-of-day routine when engine washes and/or minor maintenace was required and there was no lengthy waiting for a pilot. The pilots were happy and the engineers/mechanics were happy.

I wonder, how many other helicopter operators out there allow engineers/mechanics to perform helicopter engine ground-runs. How is this administered and what are the limitations etc.?

Senior Pilot 1st Mar 2012 04:48

Mechanic fatality Orlando is a thread from 2006 where just this problem occurred, with a fatal result.

before landing check list 1st Mar 2012 05:50

With the possibility of that ground resonance situation or the possibility of a hydraulic problem resulting in the collective going up or a mis-rigged collective bungee/spring, maybe ground runs should be limited to idle unless you have an appropriately rated pilot at the controls.

Turkeyslapper 1st Mar 2012 07:47

From where I came from, the only things the engineers could ground run in the helicopter was the APU, definately not engaged rotors engines runs.

Fareastdriver 1st Mar 2012 09:19

One amusing one.

I had a shout from ops to go down and rescue some engineers who were sitting in a Puma burning and turning. I rushed out there and there were these two engineers with panic stricken faces sitting in a 330J with one engine at ground idle and the rotors slowly turning. They had got in to do a post chemo vent run and had inadvertantly started the engine and didn't know how to shut it down.

For those not familiar with the Puma there is a start panel underneath the instrument panel which has two engine switches. The first movement runs the starter motor and continuing to the spring loaded start postion starts the automatic starting cycle. To stop everything one has to position the switch back to the off position. They didn't know that; they only knew the run and off positions. They had inadvertantly move the switch to start and they were afraid to touch anything when the engine lit up.

A slight amendment to the brief for vent runs and it didn't happen again.

Devil 49 1st Mar 2012 09:54

Previous employer allowed trained and approved mechanics to do ground run-ups. My recollection is that the aircraft had to be tied down to the pad. Aircraft were routinely tied down at end of shift, etc. anyhow. Most of the maintenance there was done at night, no pilot available. Worked very well.

mtoroshanga 1st Mar 2012 10:33

For years I carried out ground runs as an engineer on various types including Bells throughout the range and non rotor engaged Alouette runs.
The criterion was that we could carry out runs on skidded aircraft without restriction. I was surprised to see that aircraft enter ground resonance as it is skid equipped however as far as I remember is equiped with dampers on the skid struts which could be the cause.
Ground running of aircraft used to be an engineers normal task, I cannot see the problem except that on entering ground resonance lifting into the hover is the first solution. I personally would be confident to do this but am sure that the way things sre now..........

twisted wrench 1st Mar 2012 12:59

Last time I was in Norway in 2006 the CHC Norway engineers ( who had the training) ran the S-92 aircraft and probably the Puma to. They did both with rotor brake on and right up to fly position runs rotors turning.

They told me they went to Flight Safety ( S92) for training on running the aircraft and any emergencies they might encounter during a ground run.

I feel with the correct training there is no reason why the engineers can not run the aircraft. Is quite common practice in the fixed wing industry.

I agree makes the pilots and engineers both happy.

Matari 1st Mar 2012 13:10

I still have my ground run authorization card (somewhere) allowing ground running of 206's up to the B212.

I do remember an exciting incident offshore when one of our mechanics was running a 206 on the deck, pulled pitch somehow and found himself 15 feet high and spinning. No choice but to point the nose down and get the thing straight.

After a few wobbly trips around the pattern he managed to set the ship down safely, no worse for wear except he was docked to junior mechanic and owned a great bar story.

His explanation was something about a lifevest being under the collective, and he tried to remove it, and oops...up came the collective. A likely story! :}

Ever since then we had to ground run with the ship tied down, offshore or onshore.

Wizzard 1st Mar 2012 13:44


I do remember an exciting incident offshore when one of our mechanics was running a 206 on the deck, pulled pitch somehow and found himself 15 feet high and spinning. No choice but to point the nose down and get the thing straight.

After a few wobbly trips around the pattern he managed to set the ship down safely, no worse for wear except he was docked to junior mechanic and owned a great bar story
.

Sorry mate you've got the date wrong, today's 1st March not 1st April!

ShyTorque 1st Mar 2012 14:47


I feel with the correct training there is no reason why the engineers can not run the aircraft. Is quite common practice in the fixed wing industry.
But fixed wings aren't flying until they're doing a rate of knots. A helicopter can be damaged very easily during a rotors turning ground run by a poorly managed cyclic position, let alone by getting airborne and losing control of it.

But if someone else gets trained up to do it so I don't have to go in on a day off or midnight (done both a lot more than once), I'd be more than happy. Provided they didn't knock the hell out of the droop stops or chop the tail off in the process. :)

SASless 1st Mar 2012 16:08

Engineers don't like Pilots twisting spanners.....Pilots should not like Engineers moving engine or flight controls.

Plus....it is job security and impacts the pay packet if you let the Engineers do Pilot duties.....just saying.

If the cab goes airborne, decides to enter Ground Resonance, or leaves a parked position firmly on the ground....who would you rather have sat at the helm...Engineer or Pilot?

ShyTorque 1st Mar 2012 16:38

Engineer! :ok:

Matari 1st Mar 2012 18:26

Wizzard, true story. PM me if you want all the details.

I Build 92's 1st Mar 2012 18:45

Old Days
 
In the old days here at Uncle Igor's, the aircraft crew chief used to perform the maintanence ground runs. We complied with the first run in the morning prior to release for test flights and any subsequent ground runs for maintanence performed, vibration adjustments or leak checks. You were required to pass a written exam and 10 starts with PIC to get signed off. I was authorized to turn S76A & B models and the UH-60A Blackhawks. While I sat left seat for many runs in the S61's, S-64's and even a RH-53D I never managed to get those on my run card! Only incident I recall was "Tail Spin Tommy" chasing a fire bottle with a Blackhawk and I had heard of 2 S58's meshing rotors unsuccesfully!! Maybe John Dixson remembers a few more.....
All was ended when the Navy decided it wasnt a good practice to let us boys play with their toys!! :=

tracker69 1st Mar 2012 19:02

caa
 
what comes to mind here is 2 things

1: When something happens what does the insurance say
2: How the Hell have the CAA not put a Stop to this

I think its wrong unless your ppl rated you should not be able to run anything

EN48 1st Mar 2012 19:15


I feel with the correct training there is no reason why the engineers can not run the aircraft.
With the correct training, even a pilot can do it! :E

ec155mech 1st Mar 2012 19:20

thats a bit narrow minded.
being an engineer myself and having permission to do rotors running ground run I find it extremely useful. and Im sure the pilots and the company appreciate not having to spend duty time on waiting around for us to do adjustments, leak checks ect. at all hours of the day.

we receive a start up course, get examined by the training captains on a regular basis. get quizzed on emergencies and procedures.

some of my coworkers have more experience in starting a helicopter let alone fly it than some of the company's FO's

so given the right training and procedures. I see absolutely no reason what so ever, that the local CAA's should put a stick in this.

if the insurance company is aware of this I do not foresee any issues.

Att SASless, thinking that engineers doing ground runs will impact the salery is IMO a bit paranoid. as we can still not do test flights. so I wouldnt worry.

AnFI 1st Mar 2012 19:30

Check ANO please
 
I think the UK CAA ANO does have a rule against it

(think it says something about being 'qualified' tho it doesn't say what that means)

Troglodita 1st Mar 2012 19:38

Flight Time
 
Doesn't ICAO now define Helicopter Flight time as Rotor Start to Rotor Stop?

:}

Trog


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