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PompeyPaul
13th Jun 2008, 08:18
Reading through the latest June pulications of AAIB it's suprising how many people are flying, and crashing, overweight. Both the PA28R at Oban and the R44 in Cumbria.

Do pilot's routinely fly overweight ? Or is it just the ones that inevitably crash.

I am always meticulous over the W&B. In a Pa28 with 2325lb MTOW is usually overweight by a few lbs with 2x 230lb men and full fuel. Yet I've witnessed people take off in that configuration.

Does everybody fly a couple of lbs over ? Or is it just the ones that crash ?

Mikehotel152
13th Jun 2008, 08:29
I suspect it's more common with smaller aircraft where the margins are slimmer with the usual configuration of 2 chaps and full fuel. I would imagine that almost every training flight in C152s where I trained takes off overweight.

Rod1
13th Jun 2008, 08:38
I think you need to separate the aircraft which crash because they are over weight and the aircraft which are found to be overweight after an accident which had nothing to do with being overweight. In the case of the Oban accident the aircraft was overweight but it is very unlikely it contributed to the accident.

I think a lack of planning tends to kill people. Lack of planning increases the likelihood of being overweight and out of balance, but it also leads to flying in poor weather, not doing a good DI, etc etc. Added to this is that some pilots have not done a W & B since qualifying. I use Navbox for my w & b and have a print out of the graph in the aircraft for refrence.

As to how frequently people fly outside W & B, it is hard to say with any accuracy. You can rarely tell by just looking as the aircraft parks up.

Rod1

dont overfil
13th Jun 2008, 09:57
MH152
You've hit the nail on the head. The attitude of many flying instructors is "It'll be alright there's a big safety margin." The student thinks this is normal.
I learned to fly in a C152 and occasionally an aerobat with even less available payload. The instructor & I were nearly 30 stone between us. With full tanks we were well overweight but the little 152s flew perfectly.
I have since discovered not all aircraft are so forgiving.
DO

NinjaBill
13th Jun 2008, 10:19
Although equally illegal, I would suggest there is a big difference between accidentally flying overweight, and not being aware of it, and with flying overweight, while knowing how much overweight you are, the position of the C of G, and the effect that this will have on aircraft performance, stability and handling

spittingimage
13th Jun 2008, 10:46
If you fly outside the certificated W&B limits, you are almost certainly operating illegally, have just compromised your insurance and appointed yourself to the role of test pilot. :eek:

Yes, the C152 and others will fly over-gross, but you are just more hostage to fortune than usual if you accept it. Out of CofG is particularly hazardous IMHO. Put the two together and ... :=

Caveat aviator.

enq
13th Jun 2008, 11:04
I recently took the decision to take off marginally (about 50lbs) overweight in a 172 on the basis that the 2.5 hour flight would leave me well within the W&B when landing at the planned time (luckily I didn't have an emergency or unplanned early landing so that panned out OK).

This left me wondering if insurance wise, had push come to shove, would the insurance be void for the entire flight or just the period of the flight when the aircraft was overweight.

It also left me wondering just how forgiving the limits are - I had a couple of female passengers who were quite uncomfortable about giving their weight & a chap who didn't know his, so short of installing scales in the club the accuracy of self report W&B info must be subject to scepticism.

Regards all, enq.

Mike Cross
13th Jun 2008, 11:06
Although equally illegal, I would suggest there is a big difference between accidentally flying overweight, and not being aware of it, and with flying overweight, while knowing how much overweight you are, the position of the C of G, and the effect that this will have on aircraft performance, stability and handling

An interesting suggestion. Without having taken it through a test flight schedule in that configuration how would you know "the effect that this will have on aircraft performance"? The W&B diagrams weren't drawn up by someone who thought "Right, weight x, C of G at y, that's going to cause it to do z." They were arrived at as a result of flight testing.

deice
13th Jun 2008, 11:40
How much overweight is TOO much overweight? How far outside the w/b graph is TOO far? This is what bothers me most about loading outside the limits. Our performance graphs don't provide this information because if they did the graphs and limits would be different. Ofcourse there's a certain safety margin which is just that, a safety margin. If you don't know the exact weight and it happens to be 100 lbs more than you think, is it going to kill you? Probably not, but calculating with 100 lbs overweight and then actually having 200 may put you in a dire situation.

Stick to the books.
As for training overweight. My god, what are we teaching people...
Perhaps 3 inches of ice on the wings is ok too.
What about 3 quarts of oil?
How high above the 1500 foot ceiling can you go before it becomes dangerous?
How about that TFR? Is 10 miles into it OK?
A 300 m grass runway, will it be enough for takeoff on a 35degC day at 5000 feet in a C150 at 100 lbs over gross?

If we don't use ALL the limits as limits all the time, how do you know which ones are OK to break, and when?

Dysonsphere
13th Jun 2008, 11:51
While training in a warrior we did w&b for steep turns etc and found out with 2 of us were both 17 stone could only carry 10 gallons of fuel and stay in the correct c0g for unusal manovering, needless to say we took tabs on 1 side as running out of fuel would have been embarrassing. Had a share in a 140 after that and was allways damm carefull on w&b as 140`s are easy to overload re Sandown last year.

Ivor_Novello
13th Jun 2008, 11:53
Like everything else, bit of common sense always helps.
Taking off 10lbs overweight from a long tarmac runway is probably not a mortal sin.
The same, on a short grass strip on a hot day, could be critical.

Just because the speed limit says 50mph, you are not gonna drive at 50 in torrential rain and heavy traffic...

The same road, no traffic, good weather, might feel extremely slow at 55..

Ivor

dont overfil
13th Jun 2008, 12:18
New rule from EASA. To maintain the rating no FI should weigh more than 70 kilos. That should improve pay and conditions for those who are left!
DO

pbrookes
13th Jun 2008, 13:01
If you take off weighing above the MTOW and have an incident that involves an insurance claim, the insurance assessor will calculate your total AUW at take-off and if an ounce (gram) over your MTOW for that flight, they will not pay out, and you may also find the CAA chasing you for flying illegally.

Families of any fatalities may also sue you/your estate for the death of their loved one and your gross negligence! Is it worth it?

gasax
13th Jun 2008, 13:09
It is very easy to create an excel chart of your aircraft w&b. It takes 10 minutes to try some 'usual' situations and explore what happens to the cofg.

I've done that for the last 3 aircraft I have flown regularly and it has given me a good feel for whether or not a detailed w&b is needed. In the vast majority of cases it has not been necessary.

On the majority of aircraft getting outside the cofg limits takes a loading that looks unusual. Overloading is really more of a performance issue - unless you are deliberately going to do things which stress the aircraft - like aeros.

One of my aircraft had a detailed set of performance curves at varying weights which would allow you to comfortably extrapolate performance beyond mauw (well to a point probably). And if you stayed inside those (granted unproven) limits you could probably fly forever without incident.

And that is the crux of the issue many small aircraft are routinely overloaded and nothing happens apart from the performance deteriorating somewhat. However try two flights back to back in the same light aircraft - extreme forward cofg and extreme rear cofg at similar-ish weights. I've done that in my present aircraft as one of those 'interesting things to do'. And it certainly was - you would barely believe it was the same aircraft. A real eye opener.

Mariner9
13th Jun 2008, 13:37
If you take off weighing above the MTOW and have an incident that involves an insurance claim, the insurance assessor will calculate your total AUW at take-off and if an ounce (gram) over your MTOW for that flight, they will not pay out

A widely held misconception on various flying forae.

The insurers would have to prove that the overweight condition was causative to the incident to avoid payment. Of course, there may be many incidents where it could be argued W&B was contributory, but equally, there will be many incidents where it has no relevance)

I am not condoning overweight flying though :=

SNS3Guppy
13th Jun 2008, 15:08
I suspect it's more common with smaller aircraft where the margins are slimmer with the usual configuration of 2 chaps and full fuel. I would imagine that almost every training flight in C152s where I trained takes off overweight.


This is not acceptable, ever.

As a flight instructor, I have no tolerance for an operation out of safe limits, or operating outside the aircraft limitations. That includes the weight and balance. A student must complete a weight and balance calculation before every flight, and it is NEVER acceptable to operate, or allow a student to operate overweight or with the center of gravity outside limits.

Particularly in the instructing arena, it's a sacred responsibility on the part of the instructor to provide an example. A student should never be given the impression, not even implied,that operation that is unsafe or illegal is in any way acceptable. It's not.

If a student wants to fly in a Cessna 152, then the numbers must work out...otherwise the student will be moving to a 172. Even if the numbers work out but performance is compromised to the point of safety (very likely at many of the airfields where I've instructed...which have 10,000' density altitude or more in the summer), then we're moving to the bigger airplane.

Overweight operation isn't acceptable in any other kind of flying operation, either. I often find that weight must be reduced for performance reasons, rather than the actual weight limits, before the weight limits are ever reached.

Codger
13th Jun 2008, 18:43
Have you actually ever had the weights confirmed?
I've come across three aircraft that were way off what the numbers were supposed to be when we actually used the scales. One of them had an actual cog way aft of datum. When I started to tear things apart I found a jackstand base, and two large wrenches that weighed 20 pound apiece, nicely wrapped in bubble wrap tied up in the tail. All in all that plane was 290 pounds empty over the 1675 that it was supposed to be. How long had that extra weight been there? How many flights had been conducted over gross and aft of allowable cog?

Johnm
13th Jun 2008, 18:50
I carry two weight and balance charts from Navbox in my flight bag.

One is me amd Mrs Johnm with full fuel and a bit of luggage and kit, the other is me and Mrs Johnm our two fat friends and tabs fuel and a bit of luggage and kit.

Both fit the profile of my Archer 2 and allow us to get across the channel happily :ok:

Fright Level
13th Jun 2008, 19:55
Using data from the POH, I made my own little A6 weight and balance forms for the two a/c I fly. With experience I found the weight calculation vital under some circumstances (eg full tanks, 2/3 or more heavy males) and the CG less so. For every flight other than solo or 2 on board with half fuel, I scribble down the weights onto my form and add them up to check I'm within the T/O and landing limits for my a/c. If the config is slightly different (couple of cases of wine to bring back from France) then I do a full CG calculation too.

If anything happened, even through no fault of one's own, this is the first thing the AAIB would be doing. If you're too lazy to know where you are in relation to the MTOW of your plane, what other shortcuts are you taking?

Gertrude the Wombat
13th Jun 2008, 20:46
so short of installing scales in the club
If there aren't any there go and buy some.

(In my club, last time I looked, they were hidden under a bookshelf, but you knew where to look if you needed them. Eg, if an instructor said "ok, do the W&B for this check flight then" you'd tell him to get on the scales.)

englishal
13th Jun 2008, 23:30
I am always within W&B....I do sometimes lose about 15 Kg though ;)

Actually, joking aside, what determines max weight? I ask because I know I have flown over weight - or rather been flown in my aeroplane over weight. When I bought the share I did a test flight, all 4 of us went on the flight. Not knowing the aeroplane at the time, the owner said it'd be ok, and it was, we were off the ground in about 200m, 4 up (Rallye 160 HP). After buying my share and calculating W&B I found that 2 large adults and full fuel would put us at about MAUW, so we must have been over weight by 100 Kg or so. Despite being overweight the CofG was withing spec (which I'd say is more important).

However there was no noticable performance loss and I was amazed at how we had performed.......so who and what determines max weight? The Seneca in the USA has a higher MAUW than a Seneca in Europe so is it always dangerous I wonder, to fly over weight?

BeechNut
14th Jun 2008, 01:33
Despite being overweight the CofG was withing spec (which I'd say is more important).

Well yes, but. For aircraft handling but there are times when performance matters... a lot. High density altitude operations come to mind. Short runways. Obstacle clearance. All those nice charts in the manual for T.O distance over a 50 ft. obstacle suppose that the aircraft will deliver specified rate of climb. Reduce that rate of climb an you can find yourself in dangerous territory. I had a sphincter-tightening experience in my previous Cherokee 140 once. There were three of us; I'm fairly heavy at 200 lb, but my two passengers were 140 and 125 lb respectively (both pilots). We were just a bit under MGTOW; field was 2500 ft, soft (sand and gravel), and had obstacles. And it was at about 2000' above sea level. And it was a hot day, about 30C. We cleared the treetops by a very uncomfortable margin.

It was one of those "I learned about flying" experiences that you'd read about in Flying magazine. I knew, roughly that at MGTOW 2500 ft was OK for the Cherokee, but I hadn't thought that only 2000 ft above sea level there would be such a performance drop. When I got home I plugged the numbers into the charts (I know: should have done that first. I now know better). Well, I was surprised to learn... the available field length/obstacle clearance distance was right on the limits for density altitude, and the soft field correction.

And that wasn't even above the maximum.

I now own a Beech Sundowner 180, and it has considerably more payload. but also, a greater fuel capacity (with two markings on the tabs for partial fuel load computation) so it requires more careful planning. At sea level, standard conditions, max all-up weight, the distance to clear a 50' obstacle is 1860 ft. I frequently fly to a 1600 ft paved strip in the Gulf of St. Lawrence. Beautiful spot. Fortunately no immediate obstacles, and usually a good stiff headwind, but it is short enough to concentrate the mind, and to make me ensure that I know I am within the performance envelope.

I also once owned a C150. Great little aircraft but with one big flaw: the ability to land in a distance way too short for takeoff! With two chaps on board, climb rate was nothing to brag about.

So, yes, to an extent CofG can be more dangerous, especially exceeding the rear limit. Assuming you can safely get it into the air, as you will have considerably less performance on take-off if you're overweight.

SNS3Guppy
14th Jun 2008, 04:21
There is no excuse for flying overweight. What the aircraft might be certificated for in another land is really quite irrelevant. Is your airplane certificated for that weight? No? Then you're not legal, and have no business exceeding the weight.

Do you know of a surety that another certifying agency has done so with or without structural reinforcements?

Weight isn't just about performance. It's very important, and often more restrictive than the max gross weight restrictions, but there are other concerns. Weight in the fuselage only contributes to a greater wing bending moment, putting more stress on the spars and skins in monocoque or semimonocoque wing. In a turn this stress is fruther compounded, and in turbulence even more so. The load is even more magnified at the upper reaches of the speed limits for the airframe. What may seem minor sitting on the ramp or a straightforward takeoff may be another matter at the design dive limit. An airplane out of the CG envelope may fly fine, but an inadvertant spin may go flat or become unrecoverable.

Regardless of the implications, if the aircraft isn't certificated to fly at that weight, and you're not legal to do so, then you should not, may not, and must not.

Lasiorhinus
14th Jun 2008, 07:47
It also left me wondering just how forgiving the limits are - I had a couple of female passengers who were quite uncomfortable about giving their weight & a chap who didn't know his, so short of installing scales in the club the accuracy of self report W&B info must be subject to scepticism.


Declaring their exact weight might be socially unacceptable for some people, but you can always remind them that they are under no obligation to get into the aircraft at all.

I find a good rule of thumb to be, accept whatever weight the person declares (provided you believe that to be reasonable - ie, a fattyboombah declaring she's 60kg is not reasonable), but add ten kilograms to their declared weight.
If your totals taking into account this buffer zone go outside, or close to your W&B limits, then get out the scales and insist on actual weights.

spinnaker
14th Jun 2008, 08:15
Interesting thread,

I wonder how many GFT's were conducted in 152's with a CAAFU examiner on board. :}

dont overfil
14th Jun 2008, 09:42
Are you suggesting an examiner must reach a certain weight before being perverted, sorry promoted to CAAFU?
DO

pbrookes
19th Jun 2008, 12:22
Mariner9,

Which insurance company do you work for?

The small print on my policy states that if I fly outside the limitations of the permit (exceeding MTOW) then the cover is withdrawn!

IO540
19th Jun 2008, 12:31
Insurance does cover negligence.

The insurer cannot (generally) prove the pilot did it intentionally, which leaves just negligence and this is covered.

The stuff where insurance will take a walk is where the paperwork is duff e.g.

- duff/expired CofA
- invalid pilot license/rating (though they will pay out if a plain PPL departs VFR into OVC002 and kills himself immediately, because flying at 199ft is legal if you meet the 500ft distance rule)
- N-reg not owned by a US citizen and thus CofA is void (etc)

I don't condone over-MTOW flight of course. But technically it does work - you need to understand what happens. For small excesses, say a few % over, nothing happens, but you need more runway. Each 1% on weight means at least 2% more runway.

wsmempson
19th Jun 2008, 12:47
C of G and W & B is an interesting topic which I suspect is much overlooked, post PPL; when I initially approached my flying club to do a ppl, I did the 1st 2 lessons in a Trauma-hawk before someone pointed out that, with fuel to tabs, the CFI and I wouldn't get out of the airfield on an ISA day....so how was I ever going to sit my GFT?

I then bought a PA28 140 - which I loved to bits but, with full fuel and myself and another rugby player type in the front, it was noticeably forward of the C of G. I only did that once. How the Sandowne incident pilot thought he was going to leave the field on a hot day with 4 adults and full fuel, I'll never understand.

I now own an Arrow III and with 36 USG of fuel, you can load 4 normal adults, which removes a bit of the guesswork.

A PA28 235, by contrast, requires almost no thought to loading; With fuel to tabs, if you can physically fit it in the aircraft, it'll get off the ground.

The a/c which I think is hugely disappointing in this respect is the PA46 (in almost any guise) as you struggle to get 4 adults, bags and a decent fuel load, legally. What were piper thinking of?

IO540
19th Jun 2008, 13:14
Since the PA46 was designed for the American "a 20,000m hard runway in every town" :) market, I don't suppose Piper thought the liability was significant. Another 10 seconds with 350-500HP and you will be airborne.

The USA gets significantly more utility out of a plane which cannot do more than a few hundred nm with 4 people, than Europe with its relative scarcity of runways.

Anyway, this is one of many good things about the TB20. In 6 years, I have had to watch W&B only once, which was quite a long trip with 4 adults (me and three real fatties) when I had to depart with just 4hrs' fuel for a 2hr trip. I was not happy because the destination was likely to be fogged in (widespread) and in the end I cancelled and the subsequent mayhem (not everybody cancelled) borne out my decision. 1 W&B issue and zero crosswind-limit issues in 6 years is not bad going!!

IFollowRailways
19th Jun 2008, 13:48
The Seneca in the USA has a higher MAUW than a Seneca in Europe

There is no physical difference in the aircraft. European Senecas are invariably certified at 1999 Kg to avoid Euronav charges (> 2000 Kg).

The usual MAUW for a Seneca is 4570 lbs (2072 Kg). I assume that the operators have done their sums regarding the "loss" of 73 Kgs useful load verses Euronav charges and decided in favour of the former!

You could operate a european Seneca at the factory MAUW - There is nothing stopping you other than the paperwork - but you would then be liable for the charges

Mariner9
19th Jun 2008, 14:17
Which insurance company do you work for?

None, but have been engaged by most of the leading Underwriters as a consultant surveyor. In the Marine insurance field primarily (and dealing with considerably higher claims) but the principles are the same.

IO's comments above re insurance were (to use the modern vernacular which I usually deplore ;)) spot on :D

gingernut
19th Jun 2008, 14:43
I had a couple of female passengers who were quite uncomfortable about giving their weight & a chap who didn't know his,

It's sometimes possible to work backwards...."you are ok for this flight as long as you're under 17 stone."

Sometimes the answer is obvious, (I know, don't ass....u...me.)

Fat nacker brothers can cause concern.:)

In't there a video on youtube of an overweight cessna plunging earthwards?


http://youtube.com/watch?v=yaimogfse9c

SNS3Guppy
19th Jun 2008, 16:36
Since the PA46 was designed for the American "a 20,000m hard runway in every town" market, I don't suppose Piper thought the liability was significant. Another 10 seconds with 350-500HP and you will be airborne.

The USA gets significantly more utility out of a plane which cannot do more than a few hundred nm with 4 people, than Europe with its relative scarcity of runways.


Sounds like if you've flown in the US at all, you've never been away from the east coast.

bookworm
19th Jun 2008, 17:39
I'm confused. Mariner9 said:
The insurers would have to prove that the overweight condition was causative to the incident to avoid payment. Of course, there may be many incidents where it could be argued W&B was contributory, but equally, there will be many incidents where it has no relevance)

But IO540 said:
The stuff where insurance will take a walk is where the paperwork is duff e.g.
- duff/expired CofA

and Mariner9 says:
IO's comments above re insurance were spot on

Are you saying that if someone flies with an expired C of A, that fact would have to be causative in the loss in order for the insurers to avoid payment? Is that different from flying in violation of the limitations of the C of A?

Finally, is there a difference between the cases where the insured is dealing as a consumer and the case where the insured is a business? (My impression was that in the latter case at least, a breach of the terms would be regarded as a breach of contract and would void the indemnity. Or does that breach have to be material?)

mm_flynn
19th Jun 2008, 17:57
I have never seen an example presented of an insurer denying coverage in an accident (particularly for third party liability vs. hull insurance or injury to the pilot vs passengers) for a breach of regulation (expired CofA, flying to France on an NPPL, flying overweight, etc.). This issue of 'if you .... your insurance will be invalid and not payout' comes up regularly, but to date I have seen no referenceable example. One would expect people to sue in these circumstances and there to be some public domain information on the allegations and at least the general terms of settlement.

On the otherhand, there are probably a good number of examples of insurers not paying if the insurance has expired, the bill has not been paid, they have been materially lied to on the application, the pilot is engaged in a clear criminal activity, etc.

Pilot DAR
21st Jun 2008, 02:13
In past times, I used to trust what the experienced pilots told me about weight and balance, and particularly so, if it was their plane I was flying! I've learned my lesson, though it took a few! One C182 owner told me: "take it real careful, she's heavy today" after he had loaded it. I flew it out of a 1600 foot gravel runway. When I unloaded it, the weight had been 800 pounds overgross! I wish I could say that was the last time I did that... I stopped flying jumpers in a C185, because the jump club insisted on "one more jumper", which was more than one more jumper over gross. During a genuine flight test to investigate the weight and balance of another 185, I was told after the flight that an error had been made, and I had been 4" behind the aft limit, at gross weight. No wonder it was so hard to recover from the spins I was required to do!

So then I started to learn! For another flight test in a 185 float plane, I had it loaded with bagged gravel, all tied down in the back, to ballast me up to gross at the aft limit (spun much better within limits!). I land, and at the dock, who meets me? The authorities! Ramp check! Ha, I had the W&B form, and it was perfect!

I have approved special purpose overweight operations, but you sure have to be careful. That means the testing has been done, and the operating limitations spelled out and followed. If you have to aboart a takeoff, do the brakes have enough capacity to stop you? If you have to land right back, can the gear take to added load? Can the twin till make it out on one engine? What do you have to do if you hit a gust? Etc. There are many things to think about...

We learn that accidents rarely happen from just one cause, its the combination that gets you. W&B is a big one in the combination. It may not get you all on its own right away, but add in the engine failure, flight control failure, icing, gusty cross wind, severe turbulance, and you've really set yourself up for trouble. Then, if you're lucky, you're alive enough to try to explain why you tried that in the first place! Sometimes overgross has to happen (ferry fuel, for example). Such operations can be specifically tested and approved, there will be other limitations to keep things safe.

Otherwise, if you're going to fly overweight, you're taking about the same chances as exceeding Vne, or the manuevering limits. Sounds like you're not using the right plane of the job in the first place - there's always a bigger one somewhere!

We've all done stupid things, let's help each other learn and don't do it anymore...

smith
22nd Jun 2008, 11:24
The problem arrises in training aircraft because most of the aircraft in question were designed in the 50's and 60's when the mass of the average American was about 120-140lb's, now the mass of the average American (and Brit) is heading towards the 180-200lbs mark, meaning that we cannot take an aircraft full of fuel and passengers like they did when these aircraft were first designed.

My CPL instructor said for commercial reasons you mat have to fly slightly overweight but as long as you are forward rather than backward of the datum. He did say however it was entirely up to the commander what decision ws made.

Pilot DAR
22nd Jun 2008, 12:03
If the commander makes the decision to fly slightly overweight, he or she has descied to either misrepresent the true configuation of the aircraft on a weight and balalnce document, or to produce a true representation of the configuation, which would later be the evindence that the authorities would use to find fault, and the insurance company would use to deny a claim.

Such a decision is the same as deciding to fly with a known defect in the aircraft. You are deciding on behalf of the crew, the passengers, and aircraft owner, and the insurance company. They are all entitled to have their opinions considered. You might be willing to say in advance to each party that you are going to deliberately fly with a nav light U/S on a day only flight, but I bet you would think twice before you told each that you were going to fly the aircraft overweight!

If you need to carry members of our heavier society, either carry fewer of them, or choose a bigger plane. Also consider that nearly all aircraft design is predicated on 170 pounds per seat. That is not only for weight and balance planning, but the seat and floor strucure, and seatbelt attachements. We all know that there is reserve strength built into aircraft, but when I see a really large person in a seat wich I know was designed for a 170 pound person, I have concerns. When I see three or four large people in an airliner row, I get even more concerned.

A Cessna Caravan crash in Canada a few years back had as its root cause, the decision the pilot made to carry a person in each seat, and then embark into icing conditions. It might have worked, other than each of the persons was reported as being heavier than the standard 170 pounds, some apparently, by quite a lot. The plane was quite overweight, and the pilot decided to fly it. He de not make that decision again.

A decision to fly within the limitations is the only decision you are entitled to make, unless you are on a design flight test.

S-Works
22nd Jun 2008, 13:54
I am sure there are many flights made overweight and as such illegal. Just because people 'do it all the time' does not make it right.

An interesting choice for the Commander to be able to over ride the design authority. I would be questioning what else my CPL Instructor is misleading me on. Also if you ever get a job flying commercially please let us know who with so we can seek alternative carriers!!

tacpot
23rd Jun 2008, 12:03
If there aren't any there go and buy some.


I noticed that the local Tesco's have a small set of bathroom scales you can buy for £2.98! No excuse not to have a set. Well done Tesco :D

dont overfil
14th Jul 2008, 15:08
I see there's a thread running in the "Tech queries" section about calculating passenger weights.
It seems the airlines are probably more guilty of flying overweight than private flyers.
DO.

Gertrude the Wombat
14th Jul 2008, 15:45
It also left me wondering just how forgiving the limits are - I had a couple of female passengers who were quite uncomfortable about giving their weight & a chap who didn't know his, so short of installing scales in the club ....
Eh?? Are there really clubs that don't have them, for precisely this purpose?

Look, it's dead easy. If she won't tell you her weight it's "sorry, then we can't go flying". Simple as that. And if you suspect she's lying about her weight, then don't take her flying. There's no way I want a passenger who refuses to take my safety instructions seriously - best to find out on the ground, I think.

Pilot DAR
14th Jul 2008, 16:53
Yes,

and put a different way, you can say to such passengers:

"If I have the information to accurately calculate the total aircraft weight, I can fly it the way it was designed. Other than that, it's a test flight, and I cannot assure safety. Would you like to go on a test flight, or shall we fly it safely, the way it was designed?"

This theme also works well for passesngers who are unwilling to wait for last minute maintenance to be completed.

Pilot DAR

gpn01
15th Jul 2008, 20:07
I do a lot of flying with different people and I'm always upfront with them young & old, male and female. Always start the briefing with "ok, I get to ask you a really personal question.....how much do you weigh?" It's never been a problem as they're always told it's a safety issue. We also keep a set of scales handy if we're in any doubt (quite often being underweight in the front seat can be a problem!).

I really don't understand the attitude of pilot's who're willing to fly outside the limits of the aircraft's envelope. If you're ok to fly beyond Max AUW, are you ok to exceed VNE, G-loadings, max temps, etc, etc ? I'd be quite concerned about a pilot's judgement if he or she felt that they 'know' an aircraft better than its designer. Also be concerned if exceeding weight limits is likely to increase the fatigue rate of an airframe - so it might be fine for your flight but you've just overstressed it for the next person.

In this age of ever increasing litigation and insurers seeking any loopholes to avoid paying out, flying outside the aircraft's limits isn't worth it from a financial perspective nor from a personal responsibility viewpoint either.

Squeegee Longtail
16th Jul 2008, 13:43
...and what about older aircraft which don't perform to book figures any more?
I rented a 4 seater once, was within W&B limits and only just managed to clear the boundry fence with the stall warning blaring. That aircraft certainly wasn't.
I always added a big safety margin now on aircraft I didn't know well after that.

Final 3 Greens
16th Jul 2008, 13:50
I rented a 4 seater once, was within W&B limits and only just managed to clear the boundry fence with the stall warning blaring. That aircraft certainly wasn't.

Had a similar experience on an old tired PA28, except I rejected the takeoff as it was so sluggish in accelerating.

Went back to the club, went through the W&B with the CFI, he agreed we were were 50lbs below gross.

CFI was very decent about it and refused to charge me for the Hobbs time, as he said good airmanship lead to the reject and he wanted to encourage safe flying.

Squeegee Longtail
16th Jul 2008, 14:13
F3G - You were wise where I was not! I LEARNED ABOUT FLYING FROM THAT!!

Final 3 Greens
16th Jul 2008, 18:34
SL

Wise, I don't know - when we got halfway down a 1500m runway and the ASI was only just thinking about coming off the stops, I figured we were going by road - not a challenging decision to make :}

Pilot DAR
17th Jul 2008, 06:03
It is my opinion that the age, tiredness, or model of an aircraft are not factors in it's performance relative to others of the same type. It's maintenance condition could be a factor, if maintainers had allowed the aircraft to no longer conform to its required standards on it's type certificate data sheet. The pilot could be if he or she over/incorrectly loads it, or flies it with poor technique.

If you loaded it properly, and are flying it properly, and it is not performing, don't ask it's age, tiredness, or model, ask if conforms as it should. Low engine cylinder compression, mag timing way off, induction problems, wrong prop pitch, flying surface out of rig (among other causes) can all make a huge difference in performance. I delived a Lake LA-4-200 not long ago, which seemed a poor performer, but flew straight. It flew straight because someone had rigged out some great geometery problem, by rigging the right aileron 1.5" trailing edge up, which the other one was in trim. I would thus suspect that a wing was on incorrectly, that won't help the takeoff performance much! I snagged the plane, did not hear the outcome...

I think that flying technique can produce poor performance more quickly and obviously than overloading. Or phrased differently, an overloaded plane could be skillfully flown (but I'm not endorsing it), and produce performance which was seemingly acceptable. The PA28 cited earlier is a fine plane, but can be easily flown well behind the power curve on a poorly executed takeoff, and indeed, simply not climb at all. I have experimented with this on a frozen lake (miles long smooth flat runway). When abused, it just would not climb away with full power - stuck in ground affect. It had to be landed back at near full power. I've also been a very scared right seat passenger riding through a poorly executed takeoff in a 180hp PA28 Arrow. The only way a climbout happened in time, was that I retracted the gear. Everything about that plane was fine, it was totally poor pilot technique. Aircraft which are equipped with stabilators rather than stabilizer/elevator, seem to me to be able to get into a very high drag/stalled stabilator situation with application of lots of pitch up command. The early Cessna Cardinals had an AD associated with this.

There are many factors which go into causing a poor takeoff, don't just blame the plane, and decide not to learn what else could be better next time.

Pilot DAR

jxk
17th Jul 2008, 06:42
In the UK aircraft that previously required a 3 year CofA (known as a star-annual) needed an air-test to be conducted by a CAA test pilot or someone approved by them. Part of this test was a 5 minute climb at best rate of climb speeds, the results could then be compared with the POH figures and remedial action taken if necessary. IMO this was a good indicator of the aircraft's performance. Now similar aircraft requiring EASA ARCs are not required to perform this test.
As an aside, the Cessna 150/2 had/have an automatic write-down by the CAA of some 80 fpm (from memory) which would also naturally affect the t/o distance etc.

Final 3 Greens
17th Jul 2008, 08:30
PilotDAR

As jxk says the UK STAR annual was a tri yearly inspection and a club aircraft can add a lot of hours in 3 years, with resultant loss in engine performance (lower compression etc), so the average Joe PPL had no real way of knowing whether the aircraft would deliver book performance, other than by familiarity with the aircraft or finding a gross fault during the walk around (e.g. incorrect rigging, which I have also found)

If you look at the performance variation across an old fleet, I imagine that the standard deviation will be of greater magnitude than for a new fleet, simply because of the impact of factors such as engine state, paint finish, prop condition, hangar rash etc.

An aircraft at the negative tail of the distribution is what I would define as "tired."

I think that is what Squeegee Longtail is saying and I agree with his cautious approach.

And I do also agree with you that handling skills are a critical factor in achieving book performance.

Pilot DAR
17th Jul 2008, 14:26
I think that "old" should not be a factor in performance. Tired in this context would equal poorly maintained. I am not familiar with the 3 year C of A standards of the UK. I am aware though, that if the aircraft is being maintained as specified by it's manufacturer, it will be having inspections at intervals of about 100 hours, which will include a check of engine cylinder compression, mag timing (the two of which are probably the fastest ways to get an engine to preform less well), as well as rigging, and other defects which could rob performance. Waiting three years to inspect for these defects is just poor. and it's certainly is well within the scope (and responsibility) of the pilot to satisfy him/her self that the aircraft has a record of suitably recent maintenance, to cause the pilot to believe that such defects would have been caught.

A part of the process which is involved in the setting of maintenance intervals by manufacturers is the evaluation of the lenght of time a defect could safely go undetected, without causing a safety (performance) concern. 100 hours seems to be a general standard. Certainly annually is!

Think of an aircraft as a collection of parts all pulling together. The old aircraft could have a brand new engine and prop. I used to fly a Cessna 207 with more than 19,000 hours. Paint was smooth but poor looking. Excellent maintenance, zero time engine (though probably "old"), and prop. Performed beautifully during my many fligh tests, to as high as 17,500 feet in a hard climb.

Pilot checks the condition of the aircraft both logbooks and walk around, then flies it in accordance with the flight manual and good practice, and it's going to perform properly.

Pilot DAR

dont overfil
17th Jul 2008, 14:49
The flying school I attended some years ago bought about six fr152s new. They all performed slightly differently but one was a dog. Over the period thousands of hours use, replacement engines and propellers it was always the dog of the fleet. It was eventually written off in an accident where it failed to climb sufficiently. It presumeably always managed to scrape through the climb test!
DO.

Big Pistons Forever
17th Jul 2008, 16:05
Your average 30 to 40 yr old small Piper or Cessna will almost inevitably have an accumulation of small faults such as:

-Less than perfect rigging

-minor wing leading edge dents

-slightly undersized propeller because of loss to propeller dressing

-lower engine compressions

-Mag timing which is slightly retarded

- engine and flight instruments which have developed small errors

etc-etc

Non of the above faults are serious enough to render an aircraft unairworthy or imply poor maintainance or neglect they are just the reality in a heavily used club aircraft. Individually each item will have an insignificant effect on performance but collectively they will reduce performance which is significant on aircraft which in general do not have a lot of excess performance to begin with. All of the POH numbers are devleoped from a new aircraft flown by a factory test pilot. Therefore I think a heathy extra margin should be added to any calculated performance. I would suggest any flight that is calculated to be within the POH range but at the edge of the envelope should be looked at carefully wiht a view to finding ways to increase the margins.

Finally as an instructor I found that human nature means that everyone will sometimes get a little sloppy in their aircraft handling. Most of the time it doesn't matter if the ball is little bit out of the cage or the climb speed is 3 kts too fast but if you need to get the most out of your airplane you must fly it exactly. If you are going to be conducting a takeoff in more a demanding situation a pretakeoff self briefing reminding yourself of what you need to do is a good way to get in the right mental state so you are at the top of your game.

Chuck Ellsworth
17th Jul 2008, 16:33
What I find truly puzzling is the double standard that is so common within the flight training industry.

The industry puffs their chests about teaching it right the first time and blathers on and on about how those things first learned are those things longest remembered or something close to that description.

Yet many instructors fly Cessna 150's and 152's over gross weight when training people....why is this so common?

And more important why is it condoned?

jxk
17th Jul 2008, 17:24
Pilot DAR
I should have also mentioned that in the UK as well as the * annual there is an annual, 50hr/ 6 month checks. Compression and mag checks are made at the annual. However, if you take a look at Teledyne manuals you see that they say that a compression check is only of variable use. I still like the idea of the test flight which is a practical way of getting a feel for the real performance of the aircraft.

IO540
17th Jul 2008, 21:12
Chuck - I think the reason is that, in the UK, most people training are as broke as a rat in Baghdad. Many have to save up for each lesson, and can't have the next one until they have saved up for the next one.

Somehow, the training business has to live off this kind of scene, and it isn't easy. I walked out of one flying school due to crap (dangerous) maintenance, and that company had an AOC for public transport.

It isn't 'condoned' as such; more like the customers cannot tell.

And right now things are pretty bad here due to the big fuel price increases.

lady in red
17th Jul 2008, 21:35
Just to answer the question posed earlier about whether or not it is illegal to fly overweight - it is in breach of the ANO article 52, which is the article requiring the commander of the aircraft to ensure that the aircraft is correctly loaded, etc etc. If you are in breach of the ANO you are almost certainly in breach of your insurance policy which usually states specifically that it is a condition of the insurers' obligation to indemnify that all regulations including the ANO are complied with.

As an instructor I am always horrified at the number of people who regularly overload their C152s and PA28s. If it was a helicopter you would soon know about it if you overloaded it because you would end up overtorquing and causing significant damage. In aeroplanes, consistent overloading leads to insidious stress to the airframe and quite likely propagation of cracks and fatigue failures. Difficult to measure but I am sure that a metallurgist would come up with some scientific data.

Fortunately I do not usually compromise my student's weight and balance as I only weigh 130lbs. I also have no problem with 18 stone fatties in telling them they will have to learn on a bigger aeroplane - anyway it must be so uncomfortable trying to squeeze in to a C152 with all that bulk, let alone the discomfort for the other person being shoved in to the side of the door as Fatso overspills his seat entitlement. So if you cannot afford to learn to fly in a larger more expensive aeroplane, then I suggest a rigorous diet would be a good idea and you will also save a lot of money from eating less, which could go in to the flying money pot.

Final 3 Greens
17th Jul 2008, 22:02
PilotDAR

Can we agree on this?

Old does not necessarily = tired (e.g the 207 you mention, sounds like a nice a/c)

Tired does not necessarily = old (e.g. I have flown aircraft less than 5 years old with lots of hangar rash, big wear & tear)

Tired = does not deliver the expected performance, maybe through poor maintenance, maybe because the wear and tear has accumulated over time, like Big Pistons Forever says.

Chuck Ellsworth
17th Jul 2008, 22:56
Chuck - I think the reason is that, in the UK, most people training are as broke as a rat in Baghdad. Many have to save up for each lesson, and can't have the next one until they have saved up for the next one.

10540, actually I was referring to Canada with regard to overloading the C150/2's in flight training schools.

I have this funny streak in me that requires me to abide by the rules where possible...especially one as cut and dried as all up weight in small bug smashers.

I am of the opinion that if I bend or break one rule or regulation because it will save me some money or time I then leave myself open to pushing the envelope even further, so I try and stick to the rules.

However that is only my way of doing things, what mystifies me is how flight instructors can teach something and knowingly be outside something as basic as all up weight on a small training airplane.

And then of course we have the regulator who licenses these schools and instructors, are the regulators so dense they can't notice these infractions?

Ohhh wait a minute, the regulator is happy because the paper work says it was legal...stupid me. :ugh:

Pilot DAR
18th Jul 2008, 05:41
F3G,

Yes, we agree, old and tired are two different factors, and one is much more likely to affect performance than the other. Old is easily tolerated, and often very sought after. Tired should be tolerated in only very minor amounts. That thin prop, should be replaced, those retarded mags should be retimed, or overhauled, those low cylinders should be replaced, the dented wing really should be properly repaired, (or covered with a STOL kit! That will show you certain performance improvements, and a great safety improvement, though give up spins). Like nearly every machine ever created to perform a task, an aircraft is a consumable. It can be consumed quickly, or slowly. If you're willing to expect a little less performance, you might be able to consume it a little more before you start overhauling and replacing. But, you are still putting away the reserves right?

The aforementioned C207 was approaced by a mechanic, who, from 20 feet away said: "what a piece of junk!" This conclusion was based on really poor paint. I asked him what the defects were, and the only one he could come up with was poor paint, and worn upholstery. It performed well, but he did not know that, he judged an old, tired piece of junk based upon appearance at a distance.

If you're not willing to pay for an aircraft which is well maintained, why are you complaining about poor performance. You get what you pay for...

Pilot DAR

Big Pistons Forever
18th Jul 2008, 07:27
Pilot DAR

You are right paint can be a misleading indicator of aircraft condition , although in my experience, more often than not the airplanes that looked like a piece of junk,were junk:hmm:. I use two indicators for making snap judgements on aircraft. The condition of the windows and the condition of the aircraft belly. If the windows are not hazy,cracked, or crazed, and the belly is clean than even if the airplane looks a bit sad, it is probably well looked after.:ok:

PompeyPaul
18th Jul 2008, 08:20
You are right paint can be a misleading indicator of aircraft condition , although in my experience, more often than not the airplanes that looked like a piece of junk,were junk:hmm:. I use two indicators for making snap judgements on aircraft. The condition of the windows and the condition of the aircraft belly. If the windows are not hazy,cracked, or crazed, and the belly is clean than even if the airplane looks a bit sad, it is probably well looked after

I remember reading in the Jeremy Pratt books that you should check the fire extinguisher & medical box. If they are there and serviced then the aircraft is probably well looked after. From my brief experience of flying a limited set of different aircraft it seems to hold somewhat true.

Pilot DAR
18th Jul 2008, 13:36
I certainly agree that those four details are the type of things which would indicate the degree of care of the aircraft very well, if a quick clue is what is needed...

Pilot DAR