Help with another article please!

[Whirlybird]

Thanks again to all you lovely people who helped out with my article a couple of months ago. Now, if you aren't all sick of me....

This same editor wants an article on "The Dangers of Overloading". I said yes without thinking, then realised that apart from the problems of putting too many large people who lied about their weight in an R44, I know very little about it. Is it a problem in commercial work? Is it something you need to think about very often with turbine helicopters? Do you have any anecdotes or stories relating to overloaded helicopters (pm me if you don't want to tell these to the world!). And, R22 pilots, instructors etc, your stories are very welcome too.

Many thanks again in advance. Don't know what I'd do without you all. :)

[Ian Corrigible]

Whirls,

The underslung load 'incidents' (http://www.pprune.org/military-aircrew/488244-underslung-load-incidents.html) thread over on Mil Aircrew is an entertaining read, and has some anecdotes that may be suitable.

I/C

[Whirlybird]

Great; I'll take a look...

[212man]

I think, in simple terms, there are three types of overloading:


Above the RFM absolute TOM limits - with or without immediate consequences
Outside the RFM C of G range
Outside of the required performance range.


1. Will cause - as a minimum - reduced component life for both the airframe and engines, which may cause premature failure prior to their normal life. This may be minor, but costly - such as cracking in structural elements of the airframe - or there could be catastrophic failure at some later point in a component's life. The latter may take an entirely innocent pilot and pax load with it!

2. May not have obvious consequences, but will also include similar effects as above. In a more severe state, though, it may lead to loss of control due to lack of control authority.

3. I would think the effects are obvious, but for some graphic examples, please see the following video clips (with credit to Gary Spender's website):

Video Player » Griffin Helicopters | Mil Helicopter Crashes in the street (http://www.griffin-helicopters.co.uk/videos/playonevideo.aspx?videokey=433)

Video Player » Griffin Helicopters | A 206LT TwinRanger crashes trying to get (http://www.griffin-helicopters.co.uk/videos/playonevideo.aspx?videokey=378)

The other element to consider is that any pilot overloading an aircraft - with the exception of incorrectly manifested loads (for whatever reason) - is either a) ignorant of what they are doing or, b) recklessly ignoring limitations. You then have to consider how those traits manifest themselves in other areas of their flying!

Sorry - no anecdotes :)

[John R81]

Will you be treating "overloading" only as MAUW exceedance, or do you count loading below that but outside CoG?

I regularly fly EC120 close to MAUW and it can be intereting in gusty conditions. Down-wind taxi (in particular) can lead to running out of lever and (at worst) having to settle for a moment. Left-spot-turns can also be challenging at close to MAUW - which is why I tend to make them to the right when close to max power.

This EC120 http://www.aaib.gov.uk/cms_resources.cfm?file=/Eurocopter_EC_120B,_EI-IZO.pdf is below MAUW but loaded 5mm fwd of CoG limit. Uncommanded nose-down attitude possibly caused by wind gust did not prove to be controllable.

[S76Heavy]

I concur with 212-man.

Flying offshore our greatest risk is no. 3: outside the required performance range in case of OEI.

A short annecdote: at an offshore operator a certain Captain was considered "pedantic" by the handling agent as quite often he would refuse mailbags of 3-5 lbs because the helicopter would be above MAUW for (onshore) Take Off.

However, one bad day he (as well as his copilot and ground staff) failed to notice that a passenger got confused and joined the group travelling on his medium helicopter. They duly departed and it was not until they had been airborne for a good number of minutes that the error was spotted, an extra landing had to be planned to disembark the extra passenger and afterwards an occurrence report had to be filed.

While everybody had a good chuckle, he did exceed 1. and 3 and possibly 2.
Component life was recalculated and staff retrained but it could have ended badly if they had suffered a power failure.

Would be interested in reading the finished article.

[Capt Hollywood]

Maybe you could also address the reason WHY aircraft are sometimes overloaded.

The potential to overload our aircraft is something that occurs almost daily for me. The Jetranger is a great aircraft but in summer, with density altitudes of 5000' and passengers that routinely weigh over 100kg (220lbs), they struggle to do the job especially when the departure profile is near vertical! The client regularly asks why we only took two passengers when the aircraft has four seats. They begrudgingly accept the answer when we emphasise the safety reasons but at the end of the day the mighty dollar is the reason we are operating at the edge of the aircrafts ability instead of upgrading to an aircraft better suited to the task. In short the client expects champagne service on a light beer budget! I'm on a contract with a large oil & gas company so it's relatively easy for me to simply refuse to carry the loads in excess of MAUW, no one wants to be seen to be putting safety over profit, but not all pilots have it that easy. Unfortunately commercial pressure can be a powerful incentive to breach the rules because most of the time you'll get away with it.

CH

[Whirlybird]

Right, thank you, all becoming much, much clearer to me now. More most welcome; please keep 'em coming. Publication may not be for a month or two, and I can let you know when. However, if anyone wants me to send them a copy of the article when it's written just pm me your email address. I don't think it'll tell you much you don't already know though; many of you have much more experience than I do! My 'expertise' as a writer consists in knowing a little, picking brains of those who know more, and sounding like an expert when I'm not! :{:)

[Jack Carson]

Issues with respect to operating an aircraft outside of its prescribed weight and balance limitations are far more than just what physical effect it may have on the life of airframe and components. Many variables come into play while operating outside of published limitations. First amongst them to be considered is: Has the aircraft ever been tested in the condition or configuration? If not the following questions should be addressed.
• Are adequate control margins available to permit controlled flight throughout the flight envelope? As an example collective range may become an issue when operating above the published maximum. When increasing the gross weight limitations on the MH-53 the collective up stop was reached during takeoff thus requiring some restrictions on takeoff profiles and later physically moving the collective range. The aircraft’s light weight ability to autorotate was compromised in favor takeoff performance.
• Operating below the minimum takeoff weight as published may have similar issues.
• Lastly, operations outside the published limitations as listed the aircraft’s flight manual is in violation of the FARs. Should a mishap occur, it would not go well for the PIC if he had knowingly operated outside those published limitations.

[jellycopter]

When I was free-lancing regularly on the A109C, I got a job for an owner on the outskirts of London. The task involved collecting the helicopter from Biggin Hill, flying to collect him from about 10 minutes away then taking him to pick up his guests at the opposite side of London before dropping them at a hotel about another 15 minutes away for a spot of sunday lunch. I did the fuel calcs very carefully, as anyone who has flown the A109A/C series will be intimately familiar with. The outcome was that I'd need an intermediate refuel which I arranged to do whilst they were having lunch as it would have no impact on their schedule.

As I landed at the lunch location, I asked the owner if he wanted me to shutdown or whether he'd prefer a rotors running drop-off as I needed to refuel. This question was met with indignation from him as he expected me to shutdown and thought I was taking the p1$$ by needing to take on fuel. "Why didn't you get fuel before we left?".

The standard weight and balance response came but he wasn't impressed. What put the icing on the cake for me were his immortal words "Well, 'Dave' (the regular pilot) never has to refuel when we make this trip and we do it most weeks". (name changed to protect the guilty)

I can't remember the exact numbers now, but to make the trip with any sort of sensible reserve, would have put us 100kg over MAUM. Somewhat worryingly, 'Dave' is a well known pilot in those parts and revered in certain circles - but it wasn't the first time Dave's cavalier attitude had come to my attention. Needless to say, I didn't get invited back to fly for him; I can't say I was perturbed. I'm sure there are hundreds of similar anecdotes if you know who to ask.

JJ

(Edited for typo)

[OvertHawk]

I think most of us have a "but Dave didn't need to refuel" story...

Mine was: I was new to the area, operator and type. We were doing short duration shuttles from a feeder site to a sporting event. I was one of two pilots flying the shuttle in similar machines, except that the other guy's was float equipped and had some other extra bits and pieces so was notably heavier than mine. He was carrying the same pax loads as me but i was refuelling every 40 min and he was flying for 1:10 at least between refuels! I spent the whole time trying to figure out what i was doing wrong - answer was: nothing - i was at MAUW so.... do the maths!

Thing was... a week later the machine he had been flying for the three days at that event started throwing gearbox chips (on another pilot) and was found to be knackered - over-torqueing was considered to be the cause.

Once again - this was a "well respected" pilot who was revered within the industry.

"Hauling the @r$e" out of an airframe will very often bite some other poor sod. Don't do it and don't tolerate others that do it. The person it falls to bits around could be you or someone you care about.

OH

[John Eacott]

Whirls: the dangers of overloading, cause and/or effect? "Dave" stories will abound for effect, but cause can be due to many and various reasons pertaining to the operation as well as the aircraft. Lighter helicopters require actual weights (try that on some of the joyflight pax in a paddock in the bush!), larger stuff can get away with standard weights. Carry on cr@p, what does that add to either end of the spectrum? W & B, loading on some machines becomes critical and the moment arm takes over from MAUW as the thing to watch. iBal is a great little App to use on (for instance) the EC130 which can run out of fwd cg without blinking. The disconcerting 'bzzzz' when the load is out of limits will help to make larger pax understand why they are relegated to the back row and the more pleasant 'ding' comes up :)

NS ops many moons ago we operated 4 x 212's on rig shuttles with varying weights, seating and cg. It took me (Ops Controller for my sins) days to work out a standard load giving the expected range of loads and cg we could accept and which seats should be loaded first on each aircraft. But looking over your shoulder in a 15 seat configuration with each seat full and 3 standing passengers at night, just before pulling pitch, comes back to QA/supervision of the deck crew :rolleyes:

Similarly, in a light 212 doing field taxi runs during the day picking up and dropping off all around the Brent, I was given a manifest for 20 litres milk with two pax: HDO asked where, no worries, into the boot for the milk. Loading was done by HDA's under supervision of the HDO, so when the thumbs up came, off I went: or tried to! Cyclic on the forward stop, nose up to the sky, no chance of putting it back on without a tail strike so pull and go. After a run on landing on a bigger deck there were 200 litres of milk in the boot: I didn't have the heart to work out how far aft the cg must have been, but certainly kept a better eye on the freight loading whenever possible in future flights.

Another 'Dave' story operating an early A109AII with not much performance, into the owner's business in the Australian Alps in summertime: 5700ft AMSL, 20C, not much room for error. The manager insisted on loading the machine to sea level weights (he'd obviously been taught something along the way) and could not accept restricted loads according to the day. One particular discussion ended when he patted me on the shoulder and advised me that "when you have 'Dave's' experience you'll be able to overtemp and fly from here like him" :eek:

(No, Dave was not the other guy's name).

[John R81]

One of the reasons that I bought the EC120 was the fact that it records all excedences and the Pilot cannot cancel the flag. If you exceed MAUW and the simply pull enough pitch to lift it, and hence over-torque the machine, then you are going to get a flag, a bollocking and the bill. Same for over-temping. For this reason, I am confident of the history of the machine and the component parts and I know that if an exceedence occurs the engineers will have the correct calculations for impact on engine / gearbox life.

I agree with John E, the iBal is a splendid app. Given that you can configure it for your own aricraft - not just accept the standard machine - it is a really useful quick check.

[Hughes500]

Many moons ago at Silverstone in a 341. first trip in to pick up pax, fuellers had put in too much fuel, you can see what 's coming !
landed at the racetrack furthest pad down the FATO, turn into pad with wind now on my 7 o clock. Loaders bring fat basta.d out and put him in the front, nice blonde with 15st hubby in the back and then fat basta.d's brother. Couldnt do the maths to see if within mauw in such a short time. Picked 341 to hover with tq light just flashing, right pedal turn ac straight back on ground. Left pedal turn and a cushion creep take off followed by a lot of expletives on private frequency. Lesson well learnt to a novice cplh !!!

[chopjock]

"The Dangers of Overloading"

Yes but you can still overload without over torque / temping.
It can be down to how you fly the aircraft.

For example, taking off at max performance under mgtow is no different to the engine than taking off slightly above mgtow, still at (not above) max performance.

The damage occurs when you exceed the torque or temps, right?

So a little overloading can be done safely provided you stay within the engine / transmission limits. IMHO. :}

[Helinut]

Chopjock,

That is a pretty limited view of the hazards of "overloading". There is more to it than exceeding engine/gearbox limits.

From my experience, I think the view you express is found in some PPLs (in the UK). Basically, they "weigh" the helicopter by seeing if they can get into a ground effect hover without exceeding engine/gearbox limits. They assume that if they can, then everything is OK - It isn't.

There are a whole bunch of extra considerations that should be considered.

[Boslandew]

I'm surprised to hear a professional?? pilot blithely talking about taking off above MTOW. The figure is there for a reason, determined by the designers and engineers who built the thing. Flying outside the figures, performance/weight/whatever, listed in the manual means you're in territory which no flight/component testing has guaranteed.

In any case, succeed, and you saved, what, money/time/reputation??, although you might quite possibly kill the next poor bloke who has to fly the aircraft, fail and you kill yourself and your passengers.

Dave (the bloke who pushes above the limits due to his 'experience') is always wrong.

[Jack Carson]

Boslandew is correct. I can’t believe that more have not stepped up to express this side of the argument. We could start multiple threads for Vne, engine, torque, engine turbine temperature, engine N1or N2 exceedances. Rotor speed is another limitation that could be discussed. I am sure that there are as many stories of individuals that have operated on the incorrect side of the many published limits and not reported such having gotten away scot free with the belief that no issues existed as a result of the exceedance.

[Non-PC Plod]

Its not just the engine and gearbox that can get damaged! : undercarriage/skids, other bits of airframe attached to undercarriage/skids, transport joints, any load-bearing part of the airframe, such as where the main rotor gearbox is bolted to the roof. Just cos you havent over-temped the engine doesnt mean to say the tailboom wont fall off if you have over-stressed the airframe. Anyone who deliberately flies overweight is a liability.

[Tourist]

Plod

"Anyone who deliberately flies overweight is a liability."

Unless the circumstances warrant it.

[Thud_and_Blunder]

"Anyone who deliberately flies overweight is a liability."

Unless the circumstances warrant it.

Worked with several ex-Rhodesian Air Force Alouette/Huey pilots in the early 1980s. They had 'occasionally' operated the Aloe's above MAUM until the manufacturer's test pilot told them that - of all the limits they could exceed - going over max mass was the one thing that would prematurely b*gg*r the aircraft. They went to great lengths after that to keep below the limit, as resources weren't exactly easy to come by.

[Boslandew]

Tourist

Apart from the very rare case of taking a calculated risk to save life and accepting the possibility of some sort of failure while doing so and accepting the fact that the aircraft should be grounded for stringent checks if you succeed, I can't think of any other circumstances warranting it.

[Jack Carson]

With few possible exceptions, there are NO circumstances that warrant intentionally exceeding published limitations. There maybe emergency situations where an exceedance is required to save the machine. i.e. OEI situation or an unusual attitude recovery in close proximity to the ground. These would be categorized as emergency situations and as such limitations may be legally ignored to save the machine and its occupants. In any case all exceedances have to be documented.

[Tourist]

I think you need more imagination and to step outside your own parochial world for a bit.

What a great statement:-

"with a few possible exceptions there are no circumstances..."

That could be paraphrased as " yes there are circumstances"

[OvertHawk]

Tourist.

I think it's a bit harsh to describe someone who advocates operating an aircraft inside it's limits in all but an emergency situation as having a "parochial" outlook.

This was a question soliciting opinions for a civilian magazine article - not asking for an analysis of risk-balance for military operations.

OH

[Tourist]

Yes, probably a little harsh, but people who declare that others are a liability just because their section of aviation shouldn't and doesn't tolerate certain actions irritate me. There are many different sections of aviation, and for some the priorities change.

[Jack Carson]

The object of this thread was not the discussion of ones sensibilities with respect to when it may be OK to intentionally overload an aircraft but rather to the discuss the potential dangers of over loading an aircraft. The thread addresses by title "The Dangers of Overloading" and goes on to specifically ask if this is a problem in commercial work. There are two basic elements to the question, physical damage to the machine and potential liability. Physical damage may be categorized as either immediate obvious physical damage (wrinkled skin) or a more insidious reduction in aircraft and or component life. In either case both can be addressed if the overload situation is documented. Additional concerns surround potential legal or regulatory issues. I know of one instance where an EMS base was threatened with shut down for a 1KG error in the weight and balance computations due to an error when transferring empty weight information from the RFM to the weight and balance computer. There was no actual record of the aircraft ever being flown in an overloaded condition but to quote the FAA Operations Inspector the PIC could not actually ascertains the actual weight of his aircraft. In addition to shutting the operation down the PIC was informed that his certificate privileges may be revoked.

[SASless]

Gosh...I qualified for flying overweight from about the age of 50 onwards.....too many of the foaming ales and good curries I guess!

[Helinut]

Going back to the OP, can I suggest that the title be extended to include operating outside the C of G envelope too. As a post also mentioned, operating underweight should also be considered. It can be a real issue especially for light pilots. Operating within the mass and balance limits is the complete issue.

The recent posts have gone into a parallel universe, as far as a magazine article is concerned, surely. Presumably, the audience for this article would be normal pilots or student pilots, mainly PPLs.

[Whirlybird]

Helinut, I agree and can easily extend it to cover those issues. As for the audience, I'm not certain. The magazine is published in South Africa and aimed at the aviation industry as a whole, but is actually fairly lightweight; and I just do the helicopter bits, with a feature each month if we can come up with a topic. So I try to aim it at pilots and any other interested parties...I think!

As for where the thread is going, I never realised I'd touched a nerve with this topic; I wondered if I had enough to write 1500 words, and actually there's tons; thank you all. I'm happy for the thread to go anywhere; from my point of view I can take the relevant stuff and read the rest as background, adding to my woefully incomplete knowledge of this topic. So please, keep 'em coming!

[ralphmalph]

The comment about "weighing" an aircraft by measuring Tq in the hover reminds me about a thread on here.

There was a thread about a guy who wanted to learn to fly but thought he was too overweight. I was amazed at how many people did not have a clue about performance. One poster even mentioned how he did a check ride in an overweight aircraft "but it was fine"

Performance, thrust margin.....or the ability to do work. What ever you call it, if you are paying lip service to AUM, you are also probably clueless of blasé about how much "work" you can get out of an aircraft.

It is down to instructors to instill the correct thought process about performance and planning, a gash attitude at the beginning leads to gash unthinking pilots.

I would only overload the aircraft if it was to save a life, and after a measured decision, there was no other way to achieve the aim.

I have refused pax in Afghanistan that would take me over corrected AUM. Any extra weight would:

1. Reduce my performance available - not acceptable
2. Limit my options in an emergency-not acceptable
3. Reduce my ability to fight the aircraft-only a foolhardy, cocky, arrogant pilot would give that ammunition to your enemy.

Take away those emotive factors, and I cannot see any reason why you would choose to play on the bounds of safety. There are old pilots and bold pilots.....but no old bold pilots.

[Tourist]

ralph

Have you heard of "Operation Plum Duff"?

That was a circumstance which involved a Seaking that I am led to believe was spectacularly over it's MAUW. It was a calculated risk.

I assume since you mentiuoned Afghan that you are military or ex mil.

Saving a life is not the only reason to do something dangerous. Sometimes operational effect is worth the risk of breaking a few rules.
ie, sometimes it is worth it to take a life not save it.

The art of captaincy is knowing when and by just exactly how much to break rules/limits when the situation warrants it.

Otherwise all you would need to be the best captain ever is an encyclopedic knowledge of the rule book and it does not work that way.

Even the rule books, both civil and military recognise that excursions may be necessary and justified under certain circumstances.

[Jack Carson]

Tourist,
“Operation Plum Duff" and similarly “Operation Blue Light” were covert missions, based on operating the machines well above their normal Maximum Weight limitations from mission inception. The decision to operate these machines at increased maximum weight was a command mission decision not a unilateral decision by the aircraft commanders. Both of these missions resulted in all aircraft being destroyed during the prosecution of the mission. It is my belief that the destruction of the machines was as part of the mission plan.

[Tourist]

Jack

Oh well, then thats all right then.

Because of course the laws of physics apply differently to "command decisions" made by people who don't have to fly the helicopter than they do to unilateral pilots.:rolleyes:


The destruction of the aircraft had nothing to do with the decision to fly them overweight.

My point is merely that there are times when it is not stupid to fly outside the normal limits. Dangerous, yes. Wrong, maybe not.

[ralphmalph]

Tourist,

In today's military, even at war, the MAA and the threat of "illegal"activities would put paid to 95% of the times when people would be prepared to do such things. BOI's are rightly very critical, and the repercussions vast. Nobody now travels in helicopters in an unrestrained fashion (even them) even on operations.

We are clearly not talking about "total war" where the machine and crew are less important than the aim. The decision to load an aircraft above AUM for an OP still happens very very occasionally. The only time I am aware of the aircraft was grounded afterwards and shipped home for NDT and examination by the manufacturer.

I take your point about captaincy. Experience levels in the UK MOD for example are dropping rapidly. Ops in the sandy place are one thing (same day,same way tasking) broad and diverse experience is rare. When experience drops, supervision must increase if we cannot accept the repercussions of people "learning lessons"

I think you will find today's MOD terribly heavily regulated for that reason. In the latest CH-47 wire strike for example, the crew were allegedly flying lower than 100' in the transit. When questioned why, they were unaware (maybe) that flight below 50' for transit was only permitted in designated areas!!!

They had signed as read the Flying ORDER Book, but the reality is they all either we're not fully au fair with UK flying or just made a mistake. IMHO that is a first order skill for flying- understand the rules. A third order skill is contemplating them and applying them to a given situation. That third order of knowledge is hard to acquire. That's why people either act in ignorance or in flagrance.....leave the funky stuff to the third order guy/girl who considers carefully....with everyone...why it should happen, not the pilot who thinks "I'm just going to......."

[Tourist]

ralph

Fully agree with everything you say, and I think that our operational capability is suffering because of it.

[Non-PC Plod]

Tourist,

I take your point about exceptional do or die miltary scenarios - the "liability" I refer to is the person who does not pay due regard to the implications of breaking the limits. Having moved from the military environment to international civil and military training, I was amazed at how few people out there have ever looked at a performance graph; how many people think that if you have 12 seats, you can load 12 people in, and how many times have I ever seen anyone do a weight & balance calculation? - Not very Many!
It is these people who are the liabilities.

[Tourist]

Then I agree with you as well!

[Helinut]

Whirly,

You might like to look at MBJ's thread about heavy, hot and high with his 3D rig, for a good practical example:

www.pprune.org/rotorheads/496135-hot-heavy-landing-3d-camera-rig.html

[Whirlybird]

Thanks for that link, Helinut. Definitely food for thought.....