Weight

It's almost like the question of flying with a trace of ice on the wings (by that I mean taxing to takeoff with a trace of ice on the wings).
 
Just a side note, there are certain planes that have more than one MGTO weight. Either by changes in STC, or utility, normal, acro type of flight. The gross for one of my GA planes got a 200lb boost just by changing engine and wing tips. So, although it is technically over gross from its type cert, I feel very comfy operating over that weight. But, dont try this at home. Stick with the rules.
 
flyingcheesehead said:
I think that's what really gets people. Say you've got some guy up here in Wisconsin. He flies 250 pounds over gross on a cold winter's day and happens to be well inside CG limits, so the plane flies fine. In fact, he took off from a 3000 foot strip in flat terrain and had plenty of margin. The whole thing felt pretty good.
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The thing is, I'm pretty sure I've seen some of those planes flown at 250 over gross and they start doing strange things like developing cracks around mains and gearboxes, and door frames and the like. Weird. Then some guy like me gets asked to fly those planes with the new owner 10 years later and I worry that they are going to hit that fatigue point when we land a little rough when the starry-eyed new owner is trying to learn in his new tailwheel. I've passed on buying airplanes for that reason, and turned down a few jobs, too.

No, I don't like those "it's just a few pounds over gross" people. Not one bit.
 
If you knowingly take off one pound over gross the chief counsel of the FAA will make your head explode scanners style.

I’ve flown in Alaska for 12 years and have seen it happen multiple times.
 
flyingcheesehead said:
I think that's what really gets people. Say you've got some guy up here in Wisconsin. He flies 250 pounds over gross on a cold winter's day and happens to be well inside CG limits, so the plane flies fine. In fact, he took off from a 3000 foot strip in flat terrain and had plenty of margin. The whole thing felt pretty good.

Then he flies it to TX on a solo trip in the summer. It's hot, but it's just him, and the plane flies fine, even from a 3000 foot strip with gently rising terrain. It went just fine...

So, he feels fine with over gross and he feels fine with high DA and he feels fine with a 3000 foot strip.

Then, he gets together with his buddy in TX and offers to fly his buddy's family around their local area. He's already topped off with cheap 100LL, but he's flown 250 pounds over gross no problem before, so he loads everyone up and he's 250 over gross on a hot day and maybe isn't inside CG limits this time, and they crash.

If you stay within all the limits, there are generally some safety margins. Some are slimmer than others. When you start to go past the limits, then all of the other limits are MUCH more important.

A ferry pilot who is going to legally fly a plane over gross is also going to use the performance charts and math to figure out how much runway the plane will really use at the actual weight. They'll add a 20% fudge factor on top of that. They'll use the 50/75 rule (you need to be at 75% of takeoff airspeed by 50% of the way down the runway or you're not going to make it), and find something 40% of the way down the runway (half of the 80% of the runway they're planning on) to use as an abort point. They'll do all that again for the distance to 50 feet, and they'll use the TORA, TODA, and ASDA numbers for the runway as appropriate to ensure sufficient performance. They'll use climb performance charts and more math to see what climb rate they can expect at their actual weight, and ensure they'll be able to outclimb surrounding terrain. They'll modify procedures and configurations for various phases of flight as appropriate to ensure safety. It's not a simple matter of "well, the plane can technically fly so I can do it." There's a lot of extra work that goes into doing it right...

And part of "doing it right" is doing it with minimum necessary crew, NOT loading up a bunch of friends and family (passengers) who are placing their lives in your hands.
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Sometimes it is easy to forget that airplane performance, especially takeoff and landing performance, varies with weather conditions. When I was training for my PPL my instructor, Lee Ragsdale, gave me this challenge: Plan a non stop XC flight in your Cherokee 140 from Fredericksburg VA to Knoxville TN with forecasted wind, pressure and temperature. Plan for alternative airport stops at 1/3, 2/3 and near the end of the trip, Calculate takeoff and landing distances at all 5 airports for the highest local temperature of the day.

Here is what I learned. For any specific airplane, some runways will be too short on hot days but may be acceptable on cool or cold days. It is up to the pilot to determine which airports are acceptable or off limits today, based on prevailing weather. The flight from Fredericksburg to Knoxville started and ended at relatively low altitudes, but midway the available airports were at higher altitudes. Flight planning required that I use all but 30 minutes of fuel to get there, and the three alternative airports gave me built in safety outs in case things didn't go as expected. But before I could use them I had to know they were safe to use based on my aircraft performance and the prevailing weather.

How do you complete a plan like that if you are overweight to start with? Aircraft performance is now an unknown quantity. Perhaps some of it can be estimated but the more overweight you are the less accurate your assumptions become. It is better to stay with known gross weight and known performance.

I prefer to end all of my flights without incident. I respect the machine and it's limitations. I have nothing to prove.
 
I’ll go one step further, I prefer my flights not to just end without incident, but to be boring, I want the sightseeing experience to be the most exciting part of the flight. The word “probably” doesn’t come up during weather brief or preflight. And I never say “watch this”.
 
It’s not always about performance. Weight has a direct, measurable impact on the structure of the plane and repeated disregard for that is literally playing Russian Roulette with your life, or the life of a future operator of the aircraft. Sure, you might be really, really good at landing it softly, but it’s still a gamble, including in turbulence.
 
sarangan said:
My recommendation is to practice discipline. Build the habit of saying no. Every time you choose the conservative option, you strengthen that muscle. Aviation has a long memory, and the NTSB database is full of pilots who convinced themselves that “just this once” would be fine.
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Very well put.
 
I had an Instructor tell me that any time you are operating outside the limitations (weight, CG, Xwind, performnce, ect.) listed in the Airplane's Maunual you are now a Test Pilot.
 
www.law.cornell.edu

14 CFR § 21.197 - Special flight permits.

www.law.cornell.edu www.law.cornell.edu

20 pounds over MTOW will likely have minimal impact if within weight and balance envelope, using long runways and avoiding high hot op, similiar to at exact MTOW

That being said what’s your experience at max gross ops? I’d walk before you run
 
It's a strange question, unless it's just trolling. The aircraft has a safety envelope, and you're asking if you should fly outside that by a "smidge." Why would you? Are you delivering an organ for a dying child, and this is the *only* way? Are you at war, are lives hanging in the balance of this overweight flight?

What other corners are you cutting? Fuel reserves, personal wind minimums, logbook entries, visibility, VOR checks, oil changes, runway lengths, etc. Typically where there is smoke there is fire. If someone is bending one rule, they're almost certainly bending many.

Not a great look for a would-be CFI, I might add.

Plenty of blood was spilled to write those rules; the question shouldn't be "how much over can I go?" but rather "how much of a cushion inside that envelope do I insist on?"

Personally I don't fly over 90% of gross weight. Why? Because none of my missions are vital enough to require me to be at the very maximum, and I'd prefer not to become an NTSB report. Also, people aren't always honest about their weight, and people don't factor clothing in accurately. I don't have a scale in the hangar to humiliate people with, nor do I have a guarantee from the almighty I won't fly into some lower density altitude that isn't forecast or reported with perfect fidelity.

If you really need to go heavier man up and get a special flight permit like a professional.
 
Hengelo said:
Personally I don't fly over 90% of gross weight. Why? Because none of my missions are vital enough to require me to be at the very maximum, and I'd prefer not to become an NTSB report.
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I try to always give myself room to be under gross. When doing the forty hour phase one testing on my experimental I did fly it at gross, several times. I have had flights where I was right at the limit and the plane performed exactly as was expected and verified during flight testing.

I have heard it lamented that many students never get the experience of flying a fully loaded plane on a hot, humid day as most training is with them, instructor and some fuel. Back in the day when a lot of training was done using Cessna 150/152's most every flight was near, at, or over gross ... :)
 
There is a lot of room beyond the "minimum PPL" for expanding flying experience. Heck, there is nothing in the ACS that says you have to learn how to put fuel in your plane lol. I highly encourage people to grab their favorite CFI and experience more stuff; flying heavy, crosswind landings inside the aircraft's envelope, outside their own personal minimums. Learn how to fly to Canada, take that UPRT course you always see advertised on the FBO billboard, fly an open cockpit, or a plane without flaps, try tailwheels...

None of these require flying outside of regs, or prohibit the application of good ADM.
 
dp342b said:
Would you still fly if your weight was over by 20 pounds? I know there's maximum gross weight and a maximum take off weight. In all reality, how far over is too much. I can understand 200 pounds overweight but 20 pounds? Hell I'd burn that off before top of climb.
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Suggest you change your display name from 'dp342b' to 'Normalizing the Deviance.'
 
Hengelo said:
Personally I don't fly over 90% of gross weight.
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Flying at gross weight is not pushing any limits. It is what the manufacturer certified the aircraft at, implying it is fine for normal operations. Now, if you're in Leadville on a hot day, judgement is required, same with a short strip. But for most of us operating off of 3-5,000' paved runways in normal conditions, it isn't an issue.

Also, giving up 10% of your gross weight often means giving up 1/3 of your useful load. That wrecks the utility of most aircraft.
 
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Well… I respectfully beg to differ.

A fully loaded 767 is a TOTALLY different animal than a fully loaded A330.

WAAY before I get to legal, I try to apply common sense and experience.
 
kyleb said:
Flying at gross weight is not pushing any limits. It is what the manufacturer certified the aircraft at, implying it is fine for normal operations.
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Exactly. If 1 pound over is cheating death, then 1 pound under is perfectly safe. Rules are rules.

RyanShort1 said:
No, I don't like those "it's just a few pounds over gross" people. Not one bit.
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Why? Are they forcing you operate that way?
 
dp342b said:
Would you still fly if your weight was over by 20 pounds? I know there's maximum gross weight and a maximum take off weight. In all reality, how far over is too much. I can understand 200 pounds overweight but 20 pounds? Hell I'd burn that off before top of climb.
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Depending on the temperature, the height of the obstacle, and configuration, top of climb may be dictated by the snag of power lines or a tree branch.

For most applications, however, this is like asking if I would intentionally fly 1,980 feet horizontally from a cloud VFR in class E airspace under 10k.

Is it illegal? Yes.

Is it unsafe? in the grand scheme of things, probably not.

But if you care about integrity as a pilot and compliance with regulations, you’ll aim to be 2,020feet or more from thst cloud. And keep it below gross. Safety mindset matters. Once you start playing fast and loose with the regulations, and get away, you push further and further. Eventually the laws of physics will catch up when the regulations are ignored longe enough.
 
Nearly all the posts are concerned about taking off. A few mentioned structural and "in turbulence". I thought the max weight was set according to how heavy you could be and still expect the wings to stay on if you hit some bad turbulence. Being able to get off the ground doesn't mean you are at a safe weight. I think I got that idea in training for PP but it might be wrong. Seems I also learned the safe speed in turbulence was higher when heavier. ???
 
eb87f said:
I thought the max weight was set according to how heavy you could be and still expect the wings to stay on if you hit some bad turbulence.
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Max weight can be set by a ton of factors. Stall speeds of aircraft classes are regulated. Sometimes that (stall speed) drives gross weight. Climb gradient is another factor that may limit it. Structural limits certainly apply - both in keeping the wings on and in keeping the gear from folding (and plenty of other things too). Sometimes it is/was a marketing play. Set it at 2500 lb this year, then move it to 2600 lb in a few years and sell as "new and improved". There are regulatory issues too. Plenty of LSA's are certified elsewhere at more than 1320 lbs. Aeronca Champs have numerous "gross weights", largely driven by engine choice which translates to takeoff and climb performance.

Point is, there's a reason behind the specified gross weight, but the manufacturer rarely tells you which reason they used to establish the gross weight for a particular model.
 
eb87f said:
Nearly all the posts are concerned about taking off. A few mentioned structural and "in turbulence". I thought the max weight was set according to how heavy you could be and still expect the wings to stay on if you hit some bad turbulence. Being able to get off the ground doesn't mean you are at a safe weight. I think I got that idea in training for PP but it might be wrong. Seems I also learned the safe speed in turbulence was higher when heavier. ???
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You’re going to be down to max weight after about 15 minutes anyway, for most of the planes we fly, so if you can avoid massive bumpiness for that long it becomes a non-issue.
 
I just listened to an old podcast with Richard McSpadden. He was talking to a guy who got his license, then took three friends flying in a 172 at night. He ended up being 100lb over weight and decided to do touch-n-goes to get comfortable with the plane at this weight, and ultimately crashed.

He wasn't blaming anyone other than himself, but he did mention listening to older pilots say things like, "they build a fudge factor into those numbers". We have to be careful saying things like this around young, impressionable pilots. On the 182, I've even been known to say if the doors will close, it will fly. Not really true.
 
Lowflynjack said:
I just listened to an old podcast with Richard McSpadden. He was talking to a guy who got his license, then took three friends flying in a 172 at night. He ended up being 100lb over weight and decided to do touch-n-goes to get comfortable with the plane at this weight, and ultimately crashed.
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Human ballast? Now we're talking about the 99th percentile of poor decision making. I tested both of my RV's to about 5% over Van's recommended weight and all the way (perhaps very slightly past) the recommended CG limits. Putting 700 pounds of sandbags in the RV-10 pretty much sucked, but living, breathing ballast? YGBSM.
 
eb87f said:
Nearly all the posts are concerned about taking off. A few mentioned structural and "in turbulence". I thought the max weight was set according to how heavy you could be and still expect the wings to stay on if you hit some bad turbulence. Being able to get off the ground doesn't mean you are at a safe weight. I think I got that idea in training for PP but it might be wrong. Seems I also learned the safe speed in turbulence was higher when heavier. ???
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The published turbulence penetration speed is at max weight, but the proper speed decreases as weight decreases. The same vertical gust that will hit 3.8g at max weight will end up with a higher load factor at lighter weights, so the speed needs to be limited to keep the effect of that same vertical gust within load limits for the airplane.
 
sarangan said:
This is one of those classic slippery-slope issues in aviation. Many of our rules are written as hard lines, but in day-to-day flying they can start to feel soft. The danger is that if you keep nudging the boundary - just a little here, just a little there - eventually the margin disappears, and statistics take over.

Take the 30-minute fuel reserve. The airplane doesn’t stop flying at 29 minutes. Similarly, will your passengers die if you skip your three takeoffs and landings prior to carrying passengers? But those requirements exist to protect margins, not to test how close we can get to them.

My recommendation is to practice discipline. Build the habit of saying no. Every time you choose the conservative option, you strengthen that muscle. Aviation has a long memory, and the NTSB database is full of pilots who convinced themselves that “just this once” would be fine.
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I find that the best way to keep myself from making a bad decision is to first recognize that it's a potentially bad decision... And then think about what it would feel like to be about to crash and die as a result of that situation, knowing that it's too late to change it but also knowing that there were other solutions that I didn't do and I'm about to die and kill my passengers and it's my fault. That provokes a pretty powerful feeling that is an excellent antidote to decisions that don't seem so monumental when you're making them, but in reality they may be.

Barrett50 said:
Just a side note, there are certain planes that have more than one MGTO weight. Either by changes in STC, or utility, normal, acro type of flight. The gross for one of my GA planes got a 200lb boost just by changing engine and wing tips. So, although it is technically over gross from its type cert, I feel very comfy operating over that weight. But, dont try this at home. Stick with the rules.
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But when you get an STC, you're effectively changing the type certificate for that particular aircraft, and the owner of the STC has had to go through the process to prove that the plane will still fly within certification limits at the higher gross weight. It doesn't mean that you can take a plane without that engine and wingtips and load it to the same weight and expect the same result.

William Pete Hodges said:
Sometimes it is easy to forget that airplane performance, especially takeoff and landing performance, varies with weather conditions.
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And weight! One thing that's "fun" about my plane is that if I time it right, I can add 80 gallons (480 pounds) of fuel, and change my gross weight by nearly 18% (if I'm solo) in a matter of a few minutes. It's very noticeable how much performance changes when I take off again.

Another eye-opener that was very useful to add to my bag of experience was taking off from Leadville in a normally aspirated 182 that I had several hundred hours in. At MGW and our usual sub-1000-foot home field elevation, expected ground roll would be around 600 feet. In Leadville on a hot summer day (density altitude of 12,200!) the ground roll was over 2000 feet, over 3 TIMES what "normal" was.

eb87f said:
Nearly all the posts are concerned about taking off. A few mentioned structural and "in turbulence". I thought the max weight was set according to how heavy you could be and still expect the wings to stay on if you hit some bad turbulence. Being able to get off the ground doesn't mean you are at a safe weight.
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Max weight is set based on many different factors - And you don't know what they are, at least for the vast majority of planes, so you don't know how your bad decision will bite you.
 
I'd prefer not to but if i'm flying distance and that's full tanks, probably, that 20lbs would be used within 3 minutes anyway. would also depend on the airport, here in houston, it fits, it flies, leadville i'm probably bringing out the scales.
 
The funny thing about aircraft W&B is that the W is almost always underestimated from the actual weight. So 20 lb over is maybe 50 lb over or even more. Plus, did you really add up all the extra weight from the tools and other crap loaded in your plane? Couple that with an engine that doesn't put out book power anymore, piloted by an owner who isn't test-pilot quality, at ambient conditions that are not "standard," where is your safety margin at? If you have to fly over-gross to get utility out of our plane, you have the wrong plane.
 
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