Should I be scared -- C172 over Gross

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 never advise a pilot to load any airplane over gross.
I will tell you that the big killer in these situations is the cg
location, especially the aft cg.
Tell you what; instead of my "advising you" on what to do specifically
with this flight, let me suggest to you that you run a weight and
balance for this aircraft at full tanks, THEN run the same pax and
baggage loading figuring 1/4 tanks, just to see what this does to the cg.


--
Dudley Henriques

Dudley Henriques wrote:
Tell you what; instead of my "advising you" on what to do specifically
with this flight, let me suggest to you that you run a weight and
balance for this aircraft at full tanks, THEN run the same pax and
baggage loading figuring 1/4 tanks, just to see what this does to the cg.

I did. CG is pretty much center of the acceptable range.
C172 410lbs in the front seats, 170lbs in the back, 30lbs in the baggage
area, fuel to tabs -- CG is "good". Same situation, empty fuel. CG
good too.

A lot of ppl are talking about CG issues. Hey maybe I better check my
math before I fly this thing!

tman wrote:
I did. CG is pretty much center of the acceptable range.
C172 410lbs in the front seats, 170lbs in the back, 30lbs in the baggage
area, fuel to tabs -- CG is "good". Same situation, empty fuel. CG
good too.

A lot of ppl are talking about CG issues. Hey maybe I better check my
math before I fly this thing!


That's because CG is particularly critical when you're heavy. That's one of the
reasons I used to prefer the PA-32 over the C-210 for my runs to the islands.
The PA-32s all have this huge baggage compartment aft of the engine but forward
of the passenger compartment. It allowed me to stuff it full of the heaviest
crap I had to carry. Then loading all the beef in the back would leave me with
a quite acceptable CG. 6 people, baggage, full fuel (didn't mean to do that)
and hot summer day. Slow climbing but I eventually waddled up to 8,000 feet and
had a completely normal flight from that point on.

OTOH, I once took four folks down to Florida in a modified C-172 that had 180 HP
and a constant speed prop. The lardasses in the back threw me into an aft CG
situation that was acceptable until I got 20 degrees of flaps down; then I
didn't have enough trim authority to get all the pressure off the yoke. I had
to muscle it in... a rather uncomfortable situation for a fingertip kind of
flier. Sure did flare easily though...

Somebody said something about you've never carried four passengers in a C-172?
If that's the case I take back what I said earlier about making the flight. You
definitely want to take a few rides around the local area with some folks in the
back... it's not the same as just 2 guys in the front.

The other thing to consider is the very limited baggage space of the C-172.
When you pack it, you want the load as forward as you can make it. As the arm
gets longer, it's amazing the effect of weight back there.

I'm not much for experimenting heavily (pardon the pun) when I have only limited
experience. Will the C-172 fly 50 or even 100 lbs overgrossed? I know it will.
I also know I wouldn't want an inexperienced pilot behind the controls when I
did it. And a cold day would be helpful.



--
Mortimer Schnerd, RN
mschnerdatcarolina.rr.com

tman wrote:
Dudley Henriques wrote:
Tell you what; instead of my "advising you" on what to do specifically
with this flight, let me suggest to you that you run a weight and
balance for this aircraft at full tanks, THEN run the same pax and
baggage loading figuring 1/4 tanks, just to see what this does to the cg.

I did. CG is pretty much center of the acceptable range.
C172 410lbs in the front seats, 170lbs in the back, 30lbs in the baggage
area, fuel to tabs -- CG is "good". Same situation, empty fuel. CG
good too.

A lot of ppl are talking about CG issues. Hey maybe I better check my
math before I fly this thing!

For your scenario, as long as the fuel burn doesn't alter the cg to a
dangerous area your main concern is the over gross condition.
I should note that you might well be flying an aircraft down the line
someday where the fuel burn COULD be a cg altering consideration. This
was why I had you do both W&B :-)

There are several ways to approach this situation and all of them are
relevant.
The prime condition for me would be the insurance condition. You should
consider that in the event of an accident...ANY accident, even one not
involving the over gross condition, the aircraft insurance could most
certainly become an issue post accident because of the over gross condition.

Your training and skill at handling an over gross airplane, even one
"just a tad over gross" should be a consideration.

As PIC, you are asking your Pax to fly with you in an aircraft that is
over gross at takeoff; something that you might wish to reconsider.

Bottom line for me advice wise is that for some pilots, the airplane
won't necessarily fall out of the sky at 40lbs over gross, but are you
one of these pilots, and secondly, have you considered the rest of the
above factors?
The decision as PIC is yours. Make it a wise one.
--
Dudley Henriques

tman wrote:
Dudley Henriques wrote:
Tell you what; instead of my "advising you" on what to do specifically
with this flight, let me suggest to you that you run a weight and
balance for this aircraft at full tanks, THEN run the same pax and
baggage loading figuring 1/4 tanks, just to see what this does to the cg.

I did. CG is pretty much center of the acceptable range.
C172 410lbs in the front seats, 170lbs in the back, 30lbs in the baggage
area, fuel to tabs -- CG is "good". Same situation, empty fuel. CG
good too.

A lot of ppl are talking about CG issues. Hey maybe I better check my
math before I fly this thing!

This must be one heavy C172. Most 172s I've flown had a useful load of
~840 lbs. Even with full fuel, this leaves almost 600 lbs of payload.
If you are 100 lbs over gross with fuel at the tabs and 610 lbs of
payload, it sounds like this is either one heavy 172 or you have fuel
tanks with greater than 42 gallon capacity.

Matt

"tman" inv@lid wrote in message ...
Dudley Henriques wrote:
Tell you what; instead of my "advising you" on what to do specifically with this flight, let me suggest to you that
you run a weight and balance for this aircraft at full tanks, THEN run the same pax and baggage loading figuring 1/4
tanks, just to see what this does to the cg.

I did. CG is pretty much center of the acceptable range.
C172 410lbs in the front seats, 170lbs in the back, 30lbs in the baggage area, fuel to tabs -- CG is "good". Same
situation, empty fuel. CG good too.

A lot of ppl are talking about CG issues. Hey maybe I better check my math before I fly this thing!


Typical for a 172... Most are forward of the forward CG with full tanks, 2 standard folks up front, and nothing at all
in the back seats or baggage area.

"Dudley Henriques" wrote in message
...
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 never advise a pilot to load any airplane over gross.
I will tell you that the big killer in these situations is the cg
location, especially the aft cg.
Tell you what; instead of my "advising you" on what to do specifically
with this flight, let me suggest to you that you run a weight and balance
for this aircraft at full tanks, THEN run the same pax and baggage loading
figuring 1/4 tanks, just to see what this does to the cg.


--
Dudley Henriques

Making a Tail Skidder out of a 172 even a 182 when the pilot gets out is
fun!!!! 30% over gross Extreme Aft CG Utterly Priceless and FUN!!! But all
in a days work.

Here is a sample for a PA28...
http://aircraftdelivery.net/ferrypil...nkedpermit.pdf

Will scan in a 172 and 182 when I have time...

Don't fly over Gross unless approved to do so and have been instructed on
techniques you can end up a wet stain on the ground.

"NW_Pilot" wrote in message
. ..

"Dudley Henriques" wrote in message ...
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 never advise a pilot to load any airplane over gross.
I will tell you that the big killer in these situations is the cg location, especially the aft cg.
Tell you what; instead of my "advising you" on what to do specifically with this flight, let me suggest to you that
you run a weight and balance for this aircraft at full tanks, THEN run the same pax and baggage loading figuring 1/4
tanks, just to see what this does to the cg.


--
Dudley Henriques

Making a Tail Skidder out of a 172 even a 182 when the pilot gets out is fun!!!! 30% over gross Extreme Aft CG Utterly
Priceless and FUN!!! But all in a days work.

Here is a sample for a PA28...
http://aircraftdelivery.net/ferrypil...nkedpermit.pdf

Will scan in a 172 and 182 when I have time...

Don't fly over Gross unless approved to do so and have been instructed on techniques you can end up a wet stain on the
ground.



I remember a C-177 loaded to the gills, bound for HNL from OXR, and they were about 500' up by the time they crossed the
shoreline...

On Apr 18, 1:27*am, Dudley Henriques 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 never advise a pilot to load any airplane over gross.
I will tell you that the big killer in these situations is the cg
location, especially the aft cg.
Tell you what; instead of my "advising you" on what to do specifically
with this flight, let me suggest to you that you run a weight and
balance for this aircraft at full tanks, THEN run the same pax and
baggage loading figuring 1/4 tanks, just to see what this does to the cg.

--
Dudley Henriques- Hide quoted text -

I was taught to do c of g calcs with the fuel I was carrying and MT.
For a while I did this religously , and then after making up my own
weight and balance calculator and playing around for ages with
different combinations of fuel , pax and baggage, I found that for the
172N and Warriors I was flying , you could not put the c of g
outside the envelope by burning fuel. ( that is if the c of g is
inside the evelope with fuel , it will stay inside as you burn
fuel ). In both aircraft the c of g comes forward as you burn fuel
but the allowable c of g also comes forward as you lower the weight.
It may ( probably is ) different in other types. But you can
learn alot by playing around with your aircraft weight and balance
calcs. I broke mine down to a few simple rules

1. The no brainer, stay under MTOW for the density altitude ,
airfield available
2. If possible put more wt in front seats ( unusual not to anyway)

If I dont have any baggage and I know I have met the above , I know I
dont need to look any further.
If I am carrying any baggage or want to have more wt in the back seats
than front, I do the calcs
( ie hardly ever)

OK I have one other very obscure rule, ( If I have a 400 pound sumu
wrestler in the front with me, I might check the forward c of g.

Terry
PPL Downunder