Flying overweight aircraft
Flying overweight aircraft
Right then, let's see how many takers this one gets... 
Firstly, to paint the picture; consider the lower half of the GA market (piston twins, smaller twin turboprops, etc) flying on low-end corporate/air taxi/aerial survey/organ transportation/medivac type missions. That sort of thing.
The question; is flying aircraft in exceedance of their certified weight limits an accepted reality of such flying?
I've always been firmly of the view that limits are not to be exceeded. Very early in my career a manager (not mine) told me that "flying overweight aircraft is the brutal reality of [GA] ops", particularly within the particular sector of GA he worked in. Luckily, for the last fews years I've been flying in a role with a great deal of autonomy and discretion. I plan & load in a way with which I am comfortable, the client is fully onside and has no beef, Management are none the wiser - although I suspect that they'd be far happier if I scrutinised the W&B numbers less. The urge to be discreet in how I plan my flights is strong!
One of my colleagues recently confided in me that he felt overweight ops were the norm and perhaps it could be the only commercially viable way to operate some aircraft. So, am I being too stuffy?
What is the truth? Is it an unspoken reality that folks just get one with? Or are there just a few cowboys out there propagating the 'if we don't then someone else will' myth? I suspect it's somewhere in between; some companies do, some don't. Some pilots will, some won't. (Not that those that do will 'fess up here necessarily; perhaps the old "I once knew someone who..." might work.)
All thoughts shared will be appreciated.
Firstly, to paint the picture; consider the lower half of the GA market (piston twins, smaller twin turboprops, etc) flying on low-end corporate/air taxi/aerial survey/organ transportation/medivac type missions. That sort of thing.
The question; is flying aircraft in exceedance of their certified weight limits an accepted reality of such flying?
I've always been firmly of the view that limits are not to be exceeded. Very early in my career a manager (not mine) told me that "flying overweight aircraft is the brutal reality of [GA] ops", particularly within the particular sector of GA he worked in. Luckily, for the last fews years I've been flying in a role with a great deal of autonomy and discretion. I plan & load in a way with which I am comfortable, the client is fully onside and has no beef, Management are none the wiser - although I suspect that they'd be far happier if I scrutinised the W&B numbers less. The urge to be discreet in how I plan my flights is strong!
One of my colleagues recently confided in me that he felt overweight ops were the norm and perhaps it could be the only commercially viable way to operate some aircraft. So, am I being too stuffy?
What is the truth? Is it an unspoken reality that folks just get one with? Or are there just a few cowboys out there propagating the 'if we don't then someone else will' myth? I suspect it's somewhere in between; some companies do, some don't. Some pilots will, some won't. (Not that those that do will 'fess up here necessarily; perhaps the old "I once knew someone who..." might work.)
All thoughts shared will be appreciated.
Last edited by Charley; 8th Jul 2010 at 18:38. Reason: Clarification / better choice of words / remove my speculation
PPRuNe Handmaiden
Charley, when I operated GA in probably a far more brutal area than yourself, flying overweight was an absolute no no. Only "Mercy" missions could "bust the rules" but you had to have the absolute best reason for doing so.
In the UK, I cannot see why you ever need to operate overweight.
You can use the alternate rules (planning v inflight) to make it happen, but a routine flight? No.
If it's routine, send in an MOR to the CAA. Cowboys don't do any one any good.
In the UK, I cannot see why you ever need to operate overweight.
You can use the alternate rules (planning v inflight) to make it happen, but a routine flight? No.
If it's routine, send in an MOR to the CAA. Cowboys don't do any one any good.
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Having flown 'legally' overweight light aircraft the answer is no.
When one flies any aircraft over its maximum certified weight, one has now moved into preproduction test pilot activities. In single engine aircraft not only now are you totally clueless on the runway requirements for takeoff, you are also in risk of structurally failure if moderate to severe turbulence is encountered, in risk of landing gear failure on both takeoff and landing if still overweight.
With multi-engine aircraft not only are opening yourself to all the problems listed for single engine aircraft listed above, you have eliminated any engine out performance that you may have had.
One more point, let's say that someone does on an occasional basis flies an aircraft overweight. With modern all metal aircraft they are reducing the structural life of the aircraft. Just as with over stressing an aircraft by exceeding the G-loading, the aircraft metal has, for sake of argument I'll call a structural memory, while the structure may not fail when the loading is exceeded, the structural will fail someday even though the G-loading encountered is within the stated structural limits because of the time when the limits were exceeded.
So, tell your friend he is wrong, possibly dead wrong.
When one flies any aircraft over its maximum certified weight, one has now moved into preproduction test pilot activities. In single engine aircraft not only now are you totally clueless on the runway requirements for takeoff, you are also in risk of structurally failure if moderate to severe turbulence is encountered, in risk of landing gear failure on both takeoff and landing if still overweight.
With multi-engine aircraft not only are opening yourself to all the problems listed for single engine aircraft listed above, you have eliminated any engine out performance that you may have had.
One more point, let's say that someone does on an occasional basis flies an aircraft overweight. With modern all metal aircraft they are reducing the structural life of the aircraft. Just as with over stressing an aircraft by exceeding the G-loading, the aircraft metal has, for sake of argument I'll call a structural memory, while the structure may not fail when the loading is exceeded, the structural will fail someday even though the G-loading encountered is within the stated structural limits because of the time when the limits were exceeded.
So, tell your friend he is wrong, possibly dead wrong.
Thanks both. Very glad to hear that your views are pretty much the same. Especially Con's point about becoming a test pilot.
Sadly, I'm fairly sure it still happens in some places. Whilst out-and-about recently I met a guy who flies a similar type of aircraft to one in my own past, a big Cessna twin. One with a reputation for being able to carry an incredible amount of fuel. We got to talking about stuff, and I casually asked him if he ever found himself limited on how much he could actually load. "Oh, we don't usually have to worry about that." I don't think he realised I knew the type; full fuel requires a fairly empty cabin. Scary.
Sadly, I'm fairly sure it still happens in some places. Whilst out-and-about recently I met a guy who flies a similar type of aircraft to one in my own past, a big Cessna twin. One with a reputation for being able to carry an incredible amount of fuel. We got to talking about stuff, and I casually asked him if he ever found himself limited on how much he could actually load. "Oh, we don't usually have to worry about that." I don't think he realised I knew the type; full fuel requires a fairly empty cabin. Scary.
PPRuNe Handmaiden
Being pig ignorant is no excuse. In GA you are probably not always going to be "spoon fed".
So dig deep and buy a genuine copy of the POM or even AFM if required. Spend some time playing with the numbers.
Eg, find out what you can carry on the hottest day in the UK out of the shortest strip. Then you'll learn what fuel can be carried, what payload can be carried and so forth.
This will save your butt. Good luck.
Note, being conversant with the manuals on something "simple" will mean that you'll be happier to dig into the manuals in something more complex. This will definitely help you in the future.
Good luck. Again.
So dig deep and buy a genuine copy of the POM or even AFM if required. Spend some time playing with the numbers.
Eg, find out what you can carry on the hottest day in the UK out of the shortest strip. Then you'll learn what fuel can be carried, what payload can be carried and so forth.
This will save your butt. Good luck.
Note, being conversant with the manuals on something "simple" will mean that you'll be happier to dig into the manuals in something more complex. This will definitely help you in the future.
Good luck. Again.
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I used to work for a man, who on almost evey flight I flew with put the aircraft overweight with either fuel or payload.
I used to argue with him and his defence was this.
" I have 10,000hrs and twenty years in this job, I know what I am doing and this is the only way to make money in GA, I don't mind standing in court saying why I put an extra 200lbs of fuel on! I can't see any judge saying that that is wrong"
Well that day we were 800lbs over weight!
He would threaten me with my job and tell me I would never work again if I did not fly as co-pilot"
He would not let me file an MOR and as the only other FO he would have known it was me.
I hear that he flew an XLS from the States to the UK which was on the G reg, the CAA investigated and found out he did not have a type rating for it!
I also hear he had to stop being the accountable manager, chief pilot and a few other posts he held...
Justice at last for a rouge in the industry!?
I hope so...
Me, the next company I went onto and others since, I have never been asked to do anything like that, thank God... and yes I would say no!
I used to argue with him and his defence was this.
" I have 10,000hrs and twenty years in this job, I know what I am doing and this is the only way to make money in GA, I don't mind standing in court saying why I put an extra 200lbs of fuel on! I can't see any judge saying that that is wrong"
Well that day we were 800lbs over weight!
He would threaten me with my job and tell me I would never work again if I did not fly as co-pilot"
He would not let me file an MOR and as the only other FO he would have known it was me.
I hear that he flew an XLS from the States to the UK which was on the G reg, the CAA investigated and found out he did not have a type rating for it!
I also hear he had to stop being the accountable manager, chief pilot and a few other posts he held...
Justice at last for a rouge in the industry!?
I hope so...
Me, the next company I went onto and others since, I have never been asked to do anything like that, thank God... and yes I would say no!
Charley Flying overweight? No. Not on my watch.
Shiner Pilot I had the misfortune to have to fly with that clown in the early 90s. A real work of art, he was.
Shiner Pilot I had the misfortune to have to fly with that clown in the early 90s. A real work of art, he was.
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Flying Overweight
Flying overweight in corporate is rampant...
All you need to do is hang out at the pumps and hear pilot after pilot say..'top it off' and watch a clown car type of passenger load get on these aircraft...and that said, you think these guys have any clue about accel/stop, climb gradients etc ect...
They forget to get o2 for Hawaii trips...they take 3 printed charts hoping they don't have to divert...and you guessed it...they land long, have tire blow outs, hit the end of the runway trying to pull it off...or they drag it off at the end and laugh..'hey we made it'...
Playing it straight is one thing...telling your peers they need to straighten up...telling a CEO that he can't fill the plane that day is another..
I just got to the point where I just locked myself in the hangar, blinds closed, and didn't answer the door when people knocked...
All you need to do is hang out at the pumps and hear pilot after pilot say..'top it off' and watch a clown car type of passenger load get on these aircraft...and that said, you think these guys have any clue about accel/stop, climb gradients etc ect...
They forget to get o2 for Hawaii trips...they take 3 printed charts hoping they don't have to divert...and you guessed it...they land long, have tire blow outs, hit the end of the runway trying to pull it off...or they drag it off at the end and laugh..'hey we made it'...
Playing it straight is one thing...telling your peers they need to straighten up...telling a CEO that he can't fill the plane that day is another..
I just got to the point where I just locked myself in the hangar, blinds closed, and didn't answer the door when people knocked...
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Yes good advice there. Don't do it. There is one thing worst than flying a bit heavy in certain circumstances and that is exceeding the ZFW. Don'T ever, ever do that, for the structural integrity of the a/c to remain intact. You are stuck with that condition for the whole flight.
As said in the good advice above. Don'T do it. Do it once you are expected to do it always. If you continue to flyover weight your fellow aviators will also be expected to do the same, at your outfit. Make a stand and you will be respected. Break the rules and you become the bosses w***e. It's all been done before and the grave yards are full of "heroes".
As said in the good advice above. Don'T do it. Do it once you are expected to do it always. If you continue to flyover weight your fellow aviators will also be expected to do the same, at your outfit. Make a stand and you will be respected. Break the rules and you become the bosses w***e. It's all been done before and the grave yards are full of "heroes".
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No excuse for operating overweight...that said, do know pressure is applied by one or two unscrupulous ones in the UK still !
Shiner pilot - that description of the guy you came across sounds a lot like a clown that used to be roughly in the FAB direction ?? lol....if he's been removed permanently, good news indeed.
Shiner pilot - that description of the guy you came across sounds a lot like a clown that used to be roughly in the FAB direction ?? lol....if he's been removed permanently, good news indeed.
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I believe that particualr gentleman is still employed by the FAB company in question, just not as managment. He was also the chief pilot that stood up in his CRM course and said in front of everyone "we are not here to learn, simply to tick the box"!!!
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Ah, thanks for that flybypilot - 'tis indeed the person i am thinking of - shame to hear he's still around in that company in FAB as it's a good company with a lot of good people
Oh, and yes, have heard many, many times about his now infamous "ticking the box" lecture/comment - just confirms what a complete and utter tosser he really is !!
Apologies for the drift of thread......i just can't stand the lardy muppet lol
Oh, and yes, have heard many, many times about his now infamous "ticking the box" lecture/comment - just confirms what a complete and utter tosser he really is !!
Apologies for the drift of thread......i just can't stand the lardy muppet lol
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took off at max weight one day
was very surprised, as there was no SE climb.
This was the C of A Air Test for the Pa31 that I flew on the night mails, almost every night.
The climb rate was a minus number.
There was no attempt to operate below max weight, as we had almost no idea of the weight of the bulked out payload.
The fuel that we were contracted to carry ie -NO payload thus no revenue- was calculated with no great concern for realistic alternates, etc, etc.
So yes I have operated over max weight many times in AOC UK charter.
glf
This was the C of A Air Test for the Pa31 that I flew on the night mails, almost every night.
The climb rate was a minus number.
There was no attempt to operate below max weight, as we had almost no idea of the weight of the bulked out payload.
The fuel that we were contracted to carry ie -NO payload thus no revenue- was calculated with no great concern for realistic alternates, etc, etc.
So yes I have operated over max weight many times in AOC UK charter.
glf
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Gulfstreamaviator is raising a valid point. How many professional crews take-off every day with overweight, without knowing it or lacking the proper mean to determine their load?
And how many land at over MLW to avoid refuelling? I have heard of one GLEX Captain being fired for not willing to depart knowing he would land overweight at his destination...
And how many land at over MLW to avoid refuelling? I have heard of one GLEX Captain being fired for not willing to depart knowing he would land overweight at his destination...
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Firstly, to paint the picture; consider the lower half of the GA market (piston twins, smaller twin turboprops, etc) flying on low-end corporate/air taxi/aerial survey/organ transportation/medivac type missions. That sort of thing.
The question; is flying aircraft in exceedance of their certified weight limits an accepted reality of such flying?
The question; is flying aircraft in exceedance of their certified weight limits an accepted reality of such flying?
I also knew a clown selling trips on a certain jet, that could only be completed if they would have flown above the max certified level for said jet. The crew refused, so the boss did it himself with an unsuspecting new copilot. In fact there is plenty of such stories if you flew GA/exec for a while. But there is a trend for the better IMO. A lot more crews speak up against such abuse then in earlier times....
Overweight
This is an interesting thead. I could bore you with many instances I have witnessed. The answer is simple - DON'T DO IT. If you are lucky enough to get away with it you are condemning someone else to have an incident or accident when the overstressed tyres blow on a subsequent trip or even worse. Sadly sometimes the only answer is to refuse and leave your job, as I have done myself.
Take care out there, it can be difficult sometimes.
MM
Take care out there, it can be difficult sometimes.
MM
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Hello!
Yes. And therefore, after almost fifteen years of flying commercially on piston twins, I have sworn to myself (in the presence of several witnesses) that I will never, under no circumstances whatsoever, fly commercially on a piston twin again. And if I my son ever decides to be a pilot, I will spend whatever money is necessary to buy him a decent type rating that will spare him the hours-bulding-on-light-twins route into the business. It was not that bad in the nineties, but the few remaining operators of piston twins now directly compete against light jets and turboprops and are therefore forced to go to the limits (and beyond). There may be exceptions, but I have not encountered them yet.
But of course, overweight flying is not limited to piston twins and/or general aviation. The Concorde that crashed in Paris was about a tonne overweight and this seemed to be common practise as the accident investigation revealed. Not to talk about the air freight business that I only know personally from the piston twin and turboprop end, but have heard about from some heavy-metal guys that I know. And who ever went on a diving holiday will know that a diver and his tack weigh nowhere near the 212 lbs (or whatever 737 charter operators use as standard passenger weight) that the airlines calculate. I myself have carried in excess of 30kg of equipment on such trips (20 kg of which in my hand luggage to avoid being charged for extra baggage). Now imagine a 737 full of divers (may of which are quite big guys) on a three hour+ flight to Sharm el Sheikh ... I remember such flights on 737-200s that needed every inch of runway. On very long runways.
And just a reminder to all who have answered to this thread (we aren't hypocrites, are we?): Who hasn't trained on the C152 himself/herself? My first ever powered flight within legal weight and balance limits must have been my first solo... we all know, that a C152 with fuel and two adults aboard exceeds max. takeoff mass. So if I wasn't so totally anti-religious, I would perhaps quote the young man from Palestine who talked about throwing the first stone.
Happy landings,
Max (never flying overweight, because my body mass index leaves me another 20kg of reserves)
The question; is flying aircraft in exceedance of their certified weight limits an accepted reality of such flying?
But of course, overweight flying is not limited to piston twins and/or general aviation. The Concorde that crashed in Paris was about a tonne overweight and this seemed to be common practise as the accident investigation revealed. Not to talk about the air freight business that I only know personally from the piston twin and turboprop end, but have heard about from some heavy-metal guys that I know. And who ever went on a diving holiday will know that a diver and his tack weigh nowhere near the 212 lbs (or whatever 737 charter operators use as standard passenger weight) that the airlines calculate. I myself have carried in excess of 30kg of equipment on such trips (20 kg of which in my hand luggage to avoid being charged for extra baggage). Now imagine a 737 full of divers (may of which are quite big guys) on a three hour+ flight to Sharm el Sheikh ... I remember such flights on 737-200s that needed every inch of runway. On very long runways.
And just a reminder to all who have answered to this thread (we aren't hypocrites, are we?): Who hasn't trained on the C152 himself/herself? My first ever powered flight within legal weight and balance limits must have been my first solo... we all know, that a C152 with fuel and two adults aboard exceeds max. takeoff mass. So if I wasn't so totally anti-religious, I would perhaps quote the young man from Palestine who talked about throwing the first stone.
Happy landings,
Max (never flying overweight, because my body mass index leaves me another 20kg of reserves
)
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Out of curiosity, on sites such as this I have in the past heard that aircraft are designed and tested with parameters outside of the published data. I have heard from some that this added, unpublished tolerance is up to 50%.
One example I have seen used was in regards to G-limits. He said something along the lines of 'the aircraft is certified to +5G, but the testing was actually carried out to +7.5G etc.
Does this added tolerance actually exist?
I am not looking for excuses to fly overweight, incidentally. I am just wondering whether you are really pushing the limits of a Cessna 152 by flying 50lbs overweight etc. As I said it is simply out of curiosity.
One example I have seen used was in regards to G-limits. He said something along the lines of 'the aircraft is certified to +5G, but the testing was actually carried out to +7.5G etc.
Does this added tolerance actually exist?
I am not looking for excuses to fly overweight, incidentally. I am just wondering whether you are really pushing the limits of a Cessna 152 by flying 50lbs overweight etc. As I said it is simply out of curiosity.
PPRuNe Handmaiden
You can get permit to fly over weight from the manufacturer. They do issue them for long over water ferry flights.
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Hello!
In most cases it exists, but you cannot count on it. Officially, the safety factor in aircraft engineering is 1.0 (as opposed to mechanical or civil engineering where it ranges from 2 to 6 or 7), at least that's what they taught us at university (I worked in aerospace engineering in my previous life). That this is indeed the case was demonstrated by Airbus who broke the first A380 wing during static testing _before_ even reaching the required load factor. They had obviously designed it with zero added tolerance (less than zero actually...).
But knowing your safe load factors helps in making real-life judgements. Millions and millions of sucessful overweight takeoffs have demonstrated that the Cessna 152 obviously has a safety factor greater than 1.0 built into it.
And the transport category aeroplanes that I fly now are designed for a 1.6g touchdown at maximum landing mass. Not even the worst landing of any of my students has ever come close to that figure! So exceeding the landing mass by a few percent (every extra passenger adds about one percent to the landing mass of "my" aeroplane) and making a gentle touchdown at 1.2g puts much much much less load on airframe, gear and tyres than what the aeroplane is designed for. However, the brakes may not be able to cope with the extra mass because they might just be sufficient to bring the aircraft to the halt at max. landing mass.
Happy landings,
Max
Does this added tolerance actually exist?
But knowing your safe load factors helps in making real-life judgements. Millions and millions of sucessful overweight takeoffs have demonstrated that the Cessna 152 obviously has a safety factor greater than 1.0 built into it.
And the transport category aeroplanes that I fly now are designed for a 1.6g touchdown at maximum landing mass. Not even the worst landing of any of my students has ever come close to that figure! So exceeding the landing mass by a few percent (every extra passenger adds about one percent to the landing mass of "my" aeroplane) and making a gentle touchdown at 1.2g puts much much much less load on airframe, gear and tyres than what the aeroplane is designed for. However, the brakes may not be able to cope with the extra mass because they might just be sufficient to bring the aircraft to the halt at max. landing mass.
Happy landings,
Max