Gross Weight

If it is structural issues -- which I would suggest it very rarely is
-- you'll still have a huge safety margin when 5% or 10% over-weight.
You are not going to be getting that close to the 'g' envelope, and
your landings are hopefully not going to be hard enough to be given 10%
of collapsing the gear!

The answer to this is - it depends. I agree - the average flight does
not take you anywhere near the limits of the g-envelope. However,
momentary loads of 3 gees or more are not unheard of when flying in
moderate turbulence. So for a VFR flight under a stratus overcast,
sure, I wouldn't worry. For an IFR flight in cumuliform cloud, with
scattered embedded T-storms, I would reconsider. Note that while the
ultimate design load is 150% of the rated load, there is no requirement
for the structure to withstand the ultimate design load without damage.
Deformation is permissible. Repeated deformation due to excess loads
may be a problem. This all assumes the key structural components were
correctly manufactured in the first place, and have not deteriorated.
With an aging fleet, that may not be all that valid. However, I will
grant you that for a utility category aircraft, this is not an issue
worth considering.

The same issue comes up with regard to landings. Long smooth runway in
daylight and light winds, in a plane I've flown before many times? No
problem. Unfamiliar airplane and short strip with gusty crosswinds? I
think I want all the protection I can have. How tough is the gear,
anyway? When effectively the same gear is being used on an airplane
with a significantly higher gross weight, that tells you something (the
gear has plenty of margin). When you have a max landing weight lower
than the max takeoff weight, that tells you something too (the gear has
no margin - it is maxed out). Just something to think about.

Further, if you look at accident reports where over-weight operation
was a factor, I doubt you'll find many where structural issues came
into play. In fact, I can't recall reading a single one,

See the NTSB references in my reply to cwk.

Michael

"Peter R." wrote in message
...
Mike Granby wrote:

Do any of you "slippery slope" gentlemen ever exceed the speed limit on
the way to the airport?

One could argue that the speed limit is a lot more of an arbitrary number
than an aircraft's gross weight figures.

I believe you would lose that argument. Many a gross weight is set by the
marketing department so the plane performs to a competition beating
specification rather than some engineering requirement.

"Jose" wrote in message
m...
As a practical matter, if being 45 pounds over gross makes the
difference
between somebody going or being left behind, I can tell you that you'll
be as
popular as a turd in the punchbowl if you leave that person behind.

Leave some gas behind and alter your flight plan if necessary.

If your limit is 45 over gross, how far over your limit is ok?

If you take off 45 lbs. over in a 172 in how many minutes will you be at
gross?


Jose
--
Nothing takes longer than a shortcut.
for Email, make the obvious change in the address.

"Aluckyguess" wrote in message
...

"Kyle Boatright" wrote in message
...

"Thomas Borchert" wrote in message
...
Fred,

"once you go over the max weight, you are essentially a test
pilot".


As Bob pointed out, you are also illegal and not covered by insurance.


--
Thomas Borchert (EDDH)

That is NOT true. If you're insured, you're insured. Just as you're
insured driving your car even if you've got 3x the legal alchohol limit
in
your system...

KB

Not true. Car insurance is different, at least in the state of California.
There can be no exclusions the insurer has to pay, a plane is different,
they can and will void your claim if they can find a way.

Cite.

"Corky Scott" wrote

During WWII, my impression is that nearly all the escort fighters and
for sure all the bombers were over gross for every mission.

The Hiroshima bomber took off 8 tons overweight. Wow.
--
Jim in NC

"NW_PILOT" wrote in message
...
Watch the Focking Rats That Hang Around Here!! You may get an unexpected
call from the Fed's!!!

I thought you went away, No? Too bad.
--
Jim in NC

Fred Choate wrote:

Here is a topic that was of discussion at work today:

How much is too much over gross weight? For example.....the 172 has a gross
weight of 2300 lbs, but what if you are 2345 at time of takeoff.....is that
too much over, even if you are going to be burning enough fuel before your
first scheduled stop to be under weight for landing?

One pound over is too much if you want to be legal, maintain your
insurance, have the airplane perform according to published specs, etc.


What about airframe age, prop age...etc? Does it make a difference on
decision to "carry a little extra"?

Most airplanes don't perform better with age so having a tired engine
and then overloading certainly isn't going to make things any better.


I know that when I was receiving training, my instructor once had me bring 2
male adults with me to a lesson. That put 4 male adults in a 172 with full
fuel. I don't recall the specific weight we were at, but we were over
weight. The airport we flying out of had 8000' of runway, and my instructor
had me doing pattern work. The aircraft was very clumsy, and made me really
work at flying it. I didn't like that feeling at all! It was a good
training day.

Your instructor was (maybe still is) a moron.


Anyway, it was a good discussion between a few of us at work, so I thought
it might make a good topic here.

Why?

I would only knowingly fly an airplane over gross in an emergency
situation. Most airplanes are probably fine a few percent over gross,
but you may well be exploring unknown territory if you fly over gross.


Matt

"Mike Granby" wrote

Further, if you look at accident reports where over-weight operation
was a factor, I doubt you'll find many where structural issues came
into play.

Right. I seem to remember that maneuvering speed (the max speed for not
over stressing the airframe in turbulence, or hard maneuvers) is higher, for
a more heavily loaded aircraft.
--
Jim in NC

Mortimer Schnerd, RN wrote:

Jose wrote:

How much is too much over gross weight? For example.....the 172 has a gross
weight of 2300 lbs, but what if you are 2345 at time of takeoff.....is that
too much over

My answer is that anything over book is too much. It nibbles away at
flight regimes that you might need, and discover too late that you are in.



As a practical matter, if being 45 pounds over gross makes the difference
between somebody going or being left behind, I can tell you that you'll be as
popular as a turd in the punchbowl if you leave that person behind.

As a former part 135 charter and cargo pilot, I can also tell you that you
wouldn't hold on to your job for long if you hold on to your principles so
tightly. Some leeway is expected, as nobody operates in the perfect world
except the FAA... and apparently, you.

Is that why you are a former charter and cargo pilot? :-)


Matt

"Matt Whiting" wrote in message
...
I know that when I was receiving training, my instructor once had me
bring 2 male adults with me to a lesson. That put 4 male adults in a 172
with full fuel. I don't recall the specific weight we were at, but we
were over weight. The airport we flying out of had 8000' of runway, and
my instructor had me doing pattern work. The aircraft was very clumsy,
and made me really work at flying it. I didn't like that feeling at all!
It was a good training day.

Your instructor was (maybe still is) a moron.

I tend to agree with you and Bob on this. Said instructor is no longer with
us. Here is the final report text from the NTSB:

AIRCRAFT 1 PRELIMINARY REPORT

On August 17, 2004, about 2340 mountain daylight time, a Beechcraft 99
Airliner, N199GL, operated as Alpine flight 5071, was destroyed during a
collision with mountainous terrain approximately six nautical miles
northeast of Neihart, Montana, near the summit of Big Baldy Mountain. The
aircraft was operated by Alpine Aviation, Inc, dba Alpine Air, of Provo,
Utah, as a visual flight rules (VFR) non-scheduled domestic air cargo flight
under the provisions of Title 14, CFR Part 135, when the accident occurred.
The airline transport pilot-in-command and pilot rated passenger received
fatal injuries. Visual meteorological conditions prevailed, and a company
VFR flight plan was filed. The flight originated from Billings, Montana, at
2305. The flight planned destination was Kalispell, Montana (FCA). On the
evening of August 17, Salt lake Center issued an Alert Notice (ALNOT) after
radio and radar contact with the accident aircraft was lost. The following
day, about 1145 local, the aircraft wreckage was located approximately 175
feet below the summit of Big Baldy Mountain.


The "pilot rated passenger" was a friend of mine, who likely was flying the
aircraft. This gentlemen was a long time pilot, whom I took some flight
lessons from. I didn't finish with him, and I am glad I didn't. However, I
did learn things from him, one way or another....



Anyway, it was a good discussion between a few of us at work, so I thought
it might make a good topic here.

Why?

Because discussion is a great way to bring up questions, answers, things you
may not have considered before. I believe there is a heck of a lot of
knowledge out there, but the only way to get to much of it is to ask
questions, start discussions. I think to ask why to my remark is silly. Do
you ever discuss anything with your friends or co-workers? Do you ever
discuss things among other pilots? That is why...


I would only knowingly fly an airplane over gross in an emergency
situation. Most airplanes are probably fine a few percent over gross, but
you may well be exploring unknown territory if you fly over gross.


Matt

I agree with you, and there have been alot of things brought up in this
thread that have given me more information as to why. Sometimes "because
you were told not too" isn't good enough if you know what I mean.

Fred