Should I be scared -- C172 over Gross

On Apr 18, 2:43Â*pm, Bertie the Bunyip wrote:
WingFlaps wrote in news:d33d5865-938c-4cae-acb3-
:



On Apr 18, 9:20�am, Andrew Sarangan wrote:

Even if the airplane is perfectly airworthy, and all maintenance done
properly, you don't know if the engine is producing 160HP (or
whatever
the rated power for your airplane). There is no signature in the
logbook that certifies that the airplane engine has been tested and
found to produce the specified power. I have flown rentals that flew
like a 120HP Cessna instead of a 160 HP. RPM can't tell you the true
power because every airplane uses a different pitch prop.

Well if the renter is slappin' on any old prop then you should not go
there. How does a 120 HP 172 reach cruise airspeed at cruise RPM?

Coasely pitched props don't allow good static HP because the RPM doesn't
get up to where it needs to be to produce HP. That's what variable pitch
props are all about.


Yes, but my point is that cruise speed also tells you about HP on a
daily basis. As far as I know, there are only a very limited number of
approved props for each 172 variant. If you don't see the magic static
RPM as specified in the POH it's time to investigate not fly -right?

Cheers

On Apr 18, 4:02*pm, Frank Olson
wrote:
tman wrote:
Flown C172's for quite a while, and never had anybody in the back.
Now I'm planning on quite a trip, with 2 pax and luggage.

When I fill the fuel to the *tabs*, calc everyone's weight honestly and
consider baggage -- I'm 75 lbs over the 2450 gross on departure. *Maybe
100 over gross if I assume a "lie about weight" factor or some
inaccuracy with filling the tanks. *Now I'm scratching my head about
just how risky this is. *I know (others) have pushed over gross in these
planes way more under worse conditions, and have almost always gotten
away with it. *I'm inclined to just do it, and be cognizant that it will
perform differently, i.e. don't expect the same picture on climbout that
you would when solo.

Risky? *Or just roundoff error on the weight? *Here are some other factors:

This is the 160HP C172, standard.
Departure runway is 5000'.
No steep terrain to climb out of.
Plenty of alternates along with the way with 3000 runways.
Not particularly hot, humid, or high. *50 degrees at 1000 MSL for
departure or any point of landing.

I'm figuring I'm 3% over gross, causing most of my V speeds to increase
1.5%, so say -- instead of flying short final at 65 knots, I'd fly at 66
knots... OK wait I can't hold airspeed to +/- 1 knot on most days anyways.

I'm thinking through many of the factors, and it is only a "little" over
gross, only on the first hour or so of the trip. *What else should I be
aware of? *Am I dangerous?

T

I worked for a large insurance adjusting firm in Canada many years ago.
* I had to hand deliver a denial of claim letter to a small time
operator whose stock in trade was to hire low time commercial pilots and
bully them into ignoring the gross weight limits. *The aircraft in
question was a float equipped Helio Courier. *The right wing departed
the airframe during an approach to landing. *A fisherman witnessed the
whole thing. *It crashed into the trees. *Four people (including the 19
year old pilot) were killed. *We were able to determine that the
aircraft was 350 pounds over it's gross weight limit at the time of the
crash. *We calculated it was about 500 hundred ponds OG when it took
off. *The company went out of business shortly thereafter. *Their
insurance contract was cancelled "ab initio" (a Lloyd's term for "at
inception" or "from the beginning") and once that happens good luck
trying to find another provider. *Don't fly *any* aircraft over its
gross weight limit. *The pilot was held personally responsible for the
accident and had he survived, would have faced a number of liability claims.- Hide quoted text -



There seems to be an incredible amount of ignorance about what MTOW
means for the airframe structure. There is _no way_ being 350 lbs over
can tear a wing off as you describe. The aircraft is supposed to reach
it's structural limit before such failure (e.g. 4.4g = thousands of
pounds over MTOW). If the accident happened as you say I'd look very
hard at the maintenence and airframe corrosion. The problem with
moderate overloading is not structural but rather poor climb
performance and COG. For example, slap some floats on many planes and
the MTOW is immediately increased. How can that be- same engine and
wings and yet the plane can suddenly fly a higher MTOW. If half the
poasters here were correct youd expect crashes all over the place.
Commercial airlines regularaly go over MTOW because they don't weigh
the passengers. Think about it please!

Cheers

WingFlaps wrote:
On Apr 18, 4:02 pm, Frank Olson
wrote:
tman wrote:
Flown C172's for quite a while, and never had anybody in the back.
Now I'm planning on quite a trip, with 2 pax and luggage.
When I fill the fuel to the *tabs*, calc everyone's weight honestly and
consider baggage -- I'm 75 lbs over the 2450 gross on departure. Maybe
100 over gross if I assume a "lie about weight" factor or some
inaccuracy with filling the tanks. Now I'm scratching my head about
just how risky this is. I know (others) have pushed over gross in these
planes way more under worse conditions, and have almost always gotten
away with it. I'm inclined to just do it, and be cognizant that it will
perform differently, i.e. don't expect the same picture on climbout that
you would when solo.
Risky? Or just roundoff error on the weight? Here are some other factors:
This is the 160HP C172, standard.
Departure runway is 5000'.
No steep terrain to climb out of.
Plenty of alternates along with the way with 3000 runways.
Not particularly hot, humid, or high. 50 degrees at 1000 MSL for
departure or any point of landing.
I'm figuring I'm 3% over gross, causing most of my V speeds to increase
1.5%, so say -- instead of flying short final at 65 knots, I'd fly at 66
knots... OK wait I can't hold airspeed to +/- 1 knot on most days anyways.
I'm thinking through many of the factors, and it is only a "little" over
gross, only on the first hour or so of the trip. What else should I be
aware of? Am I dangerous?
T
I worked for a large insurance adjusting firm in Canada many years ago.
I had to hand deliver a denial of claim letter to a small time
operator whose stock in trade was to hire low time commercial pilots and
bully them into ignoring the gross weight limits. The aircraft in
question was a float equipped Helio Courier. The right wing departed
the airframe during an approach to landing. A fisherman witnessed the
whole thing. It crashed into the trees. Four people (including the 19
year old pilot) were killed. We were able to determine that the
aircraft was 350 pounds over it's gross weight limit at the time of the
crash. We calculated it was about 500 hundred ponds OG when it took
off. The company went out of business shortly thereafter. Their
insurance contract was cancelled "ab initio" (a Lloyd's term for "at
inception" or "from the beginning") and once that happens good luck
trying to find another provider. Don't fly *any* aircraft over its
gross weight limit. The pilot was held personally responsible for the
accident and had he survived, would have faced a number of liability claims.- Hide quoted text -



There seems to be an incredible amount of ignorance about what MTOW
means for the airframe structure. There is _no way_ being 350 lbs over
can tear a wing off as you describe. The aircraft is supposed to reach
it's structural limit before such failure (e.g. 4.4g = thousands of
pounds over MTOW). If the accident happened as you say I'd look very
hard at the maintenence and airframe corrosion. The problem with
moderate overloading is not structural but rather poor climb
performance and COG. For example, slap some floats on many planes and
the MTOW is immediately increased. How can that be- same engine and
wings and yet the plane can suddenly fly a higher MTOW. If half the
poasters here were correct youd expect crashes all over the place.
Commercial airlines regularaly go over MTOW because they don't weigh
the passengers. Think about it please!

Cheers


You are correct. Corrosion was a factor in the accident, but it was
only considered as "contributing". You're dealing with two different
things here. If you read your insurance contract it has strict
provisions when it comes to the way you operate your aircraft.
Operating it with no C of A, or in such a manner that could violate the
C of A, leaves the provider recourse to a whole host of legal actions
(up to and including cancellation of your contract). And then there's
"subrogation".

Heavy metal pilots know exactly what their aircraft weigh before they're
pushed back from the gate. It's not unusual for you to see them offload
a container or two on the longer over-water flights where fuel is a more
precious commodity. I don't doubt that many aircraft are flying close
to or above their MTOW. Common practice doesn't make it right, though.

Tman,

What else should I be
aware of?


The insurance. If something happens, you'll probably not be covered.
That and a ramp check are your major risks.

That said, performancewise, you'll likely not have a problem. However,
you need to be very aware of runway lenghts and density altitudes.
Those are the biggies, not a knot more or less in stall speed.

--
Thomas Borchert (EDDH)

In article tman inv@lid writes:
Flown C172's for quite a while, and never had anybody in the back.
Now I'm planning on quite a trip, with 2 pax and luggage.

When I fill the fuel to the *tabs*, calc everyone's weight honestly and
consider baggage -- I'm 75 lbs over the 2450 gross on departure. Maybe
100 over gross if I assume a "lie about weight" factor or some
inaccuracy with filling the tanks. Now I'm scratching my head about
just how risky this is. I know (others) have pushed over gross in these
planes way more under worse conditions, and have almost always gotten
away with it.

"almost alway gotten away with it". What of those that didn't get away
with it?

Another poster quoted a couple of NTSB accident reports. Do you want to
be the star of another one, while the rest of us say "gee, he was stupid"?

You probably won't get nailed for a few pounds over gross, but when something
else goes wrong, then you will have less margin.

Remember, the 172 used to have a MTOW of 2300 pounds. When you tell yourself
that the number has been raised, consider that you are STARTING WITH THE RAISED
VALUE.


Perhaps it is time to talk to the instructor about a few hours dual in
a C-182. Perhaps he can throw in aeronautical decision making at the
same time.

Alan

tman wrote:
Flown C172's for quite a while, and never had anybody in the back.
Now I'm planning on quite a trip, with 2 pax and luggage.

Wow thanks for all the help guys. I showed this post and thread to the
two potential pax.

Anyways, I think my weight problem is solved.

I have some questions now not on weight but on wake turbulence
avoidance. I'll be flying into the nearest local class C to meet my two
former pax that will be arriving on a RJ, then renting a car!

On Apr 18, 6:56*pm, Frank Olson
wrote:
WingFlaps wrote:
On Apr 18, 4:02 pm, Frank Olson
wrote:
tman wrote:
Flown C172's for quite a while, and never had anybody in the back.
Now I'm planning on quite a trip, with 2 pax and luggage.
When I fill the fuel to the *tabs*, calc everyone's weight honestly and
consider baggage -- I'm 75 lbs over the 2450 gross on departure. *Maybe
100 over gross if I assume a "lie about weight" factor or some
inaccuracy with filling the tanks. *Now I'm scratching my head about
just how risky this is. *I know (others) have pushed over gross in these
planes way more under worse conditions, and have almost always gotten
away with it. *I'm inclined to just do it, and be cognizant that it will
perform differently, i.e. don't expect the same picture on climbout that
you would when solo.
Risky? *Or just roundoff error on the weight? *Here are some other factors:
This is the 160HP C172, standard.
Departure runway is 5000'.
No steep terrain to climb out of.
Plenty of alternates along with the way with 3000 runways.
Not particularly hot, humid, or high. *50 degrees at 1000 MSL for
departure or any point of landing.
I'm figuring I'm 3% over gross, causing most of my V speeds to increase
1.5%, so say -- instead of flying short final at 65 knots, I'd fly at 66
knots... OK wait I can't hold airspeed to +/- 1 knot on most days anyways.
I'm thinking through many of the factors, and it is only a "little" over
gross, only on the first hour or so of the trip. *What else should I be
aware of? *Am I dangerous?
T
I worked for a large insurance adjusting firm in Canada many years ago.
* I had to hand deliver a denial of claim letter to a small time
operator whose stock in trade was to hire low time commercial pilots and
bully them into ignoring the gross weight limits. *The aircraft in
question was a float equipped Helio Courier. *The right wing departed
the airframe during an approach to landing. *A fisherman witnessed the
whole thing. *It crashed into the trees. *Four people (including the 19
year old pilot) were killed. *We were able to determine that the
aircraft was 350 pounds over it's gross weight limit at the time of the
crash. *We calculated it was about 500 hundred ponds OG when it took
off. *The company went out of business shortly thereafter. *Their
insurance contract was cancelled "ab initio" (a Lloyd's term for "at
inception" or "from the beginning") and once that happens good luck
trying to find another provider. *Don't fly *any* aircraft over its
gross weight limit. *The pilot was held personally responsible for the
accident and had he survived, would have faced a number of liability claims.- Hide quoted text -

There seems to be an incredible amount of ignorance about what MTOW
means for the airframe structure. There is _no way_ being 350 lbs over
can tear a wing off as you describe. The aircraft is supposed to reach
it's structural limit before such failure (e.g. 4.4g = thousands of
pounds over MTOW). If the accident happened as you say I'd look very
hard at the maintenence and airframe corrosion. The problem with
moderate overloading is not structural but rather poor climb
performance and COG. For example, slap some floats on many planes and
the MTOW is immediately increased. How can that be- same engine and
wings and yet the plane can suddenly fly a higher MTOW. If half the
poasters here were correct youd expect crashes all over the place.
Commercial airlines regularaly go over MTOW because they don't weigh
the passengers. Think about it please!

Cheers

You are correct. *Corrosion was a factor in the accident, but it was
only considered as "contributing". *

I hope you are suitably impressed at my insight.

You're dealing with two different
things here. *If you read your insurance contract it has strict
provisions when it comes to the way you operate your aircraft.
Operating it with no C of A, or in such a manner that could violate the
C of A, leaves the provider recourse to a whole host of legal actions
(up to and including cancellation of your contract). *And then there's
"subrogation".

The C of A on my aircraft is non terminating. What does that mean?


Heavy metal pilots know exactly what their aircraft weigh before they're
pushed back from the gate.

There we disagree. They may know cargo and baggage and fuel but not
meat.

Cheers

gatt wrote:


I take that to mean "by the time you land," but, that doesn't take into
consideration departure stalls,

Speaking of departure stalls while heavy...

This was a friend of mine, based here in CT:
http://www.ntsb.gov/NTSB/brief.asp?ev_id=20010806X01608&key=1
We lost him and five of his relatives.

This is fresh in my mind from last year:
http://www.ntsb.gov/NTSB/brief.asp?ev_id=20070917X01402&key=1
Along with four adult males, this plane had golf bags aboard, headed to
Cape Cod.

tman wrote:
tman wrote:
Flown C172's for quite a while, and never had anybody in the back.
Now I'm planning on quite a trip, with 2 pax and luggage.

Wow thanks for all the help guys. I showed this post and thread to the
two potential pax.

Anyways, I think my weight problem is solved.

I have some questions now not on weight but on wake turbulence
avoidance. I'll be flying into the nearest local class C to meet my two
former pax that will be arriving on a RJ, then renting a car!


You're ****ting me. Just because you would have been overgrossed with four
passengers now you're flying by yourself? Two others wouldn't go?

Well, maybe it's for the best. Until you get an instrument rating, your chances
of flying cross country on any particular day are no better than 50-50.



--
Mortimer Schnerd, RN
mschnerdatcarolina.rr.com

tman wrote:
tman wrote:
Flown C172's for quite a while, and never had anybody in the back.
Now I'm planning on quite a trip, with 2 pax and luggage.

Wow thanks for all the help guys. I showed this post and thread to the
two potential pax.

Anyways, I think my weight problem is solved.

I have some questions now not on weight but on wake turbulence
avoidance. I'll be flying into the nearest local class C to meet my two
former pax that will be arriving on a RJ, then renting a car!

Well, I know that must have been a bitter decision, but I think you made
the right one. Or, at least, you didn't make the wrong one, and that
makes you a better pilot.

By the way, if you plan on carrying passengers in the back, I learned
that it's a good idea to go ride in the back of somebody's 172 to feel
it from the passenger's perspective. They feel pitch changes a lot
more than you do because they're aft of the wing and CG, and when you're
flaring for landing they're seeing and feeling something different than
you are.

Have a great flight!
-c