Since we're talking electronic sensors...

Charlie wrote:
....
on most light private aircraft just how critical is the weight anyway?
do you think it might be a solution in search of a problem?
Stealth Pilot
*
*
While I'd agree with that last pair of rhetorical questions if all
pilots exercised some semblance of good judgment, perusal of accident
records will quickly reveal how critical excess weight can be.

Charlie

As I recall, FARs use 170 lbs as the standard passenger weight for
airline weight & balance calcs. It's been a while since I've seen
many males at 170 lbs.
Women at that weight can be hard to find in these parts too....

Brian W

On Fri, 15 May 2009 08:51:47 +0000, Stealth Pilot wrote:

on most light private aircraft just how critical is the weight anyway?

I agree. I would suspect that centre of gravity is more likely to cause
problems than weight for light aircraft.

do you think it might be a solution in search of a problem?

Absolutely Like the AoA sensor, pilots can get by perfectly well
without this. But it's just another tool which can add to safety, and I
enjoy thinking about this stuff... especially when I should be working on
assignments. Like right now

"Michael" wrote in message
...
On Fri, 15 May 2009 08:51:47 +0000, Stealth Pilot wrote:

on most light private aircraft just how critical is the weight anyway?

I agree. I would suspect that centre of gravity is more likely to cause
problems than weight for light aircraft.

The balance problem is not at all confined to light aircraft.

Actually, I suspect the ligh aircraft are less sensitive to balance problems
because of their relatively short fuselages and (usually) small capacity as
a fraction of gross weight.

The main advantage of heavy aircraft is that they are much more likely to
have their loads planned and secured--and also calculated for all of the
fuel distributions that might reasonably occur during the flight.

do you think it might be a solution in search of a problem?

Absolutely Like the AoA sensor, pilots can get by perfectly well
without this. But it's just another tool which can add to safety, and I
enjoy thinking about this stuff... especially when I should be working on
assignments. Like right now

"Stealth Pilot" wrote in message ...

I've heard a discussion of this and the point made was that the wings
are still flying while parked on the ground. in still air the system
would work but with a breeze, or worse in gusts, the system may never
sense the actual aircraft weight.

the other problem was calibrating the weighing (certifying the thing)
and finding really horizontal ground all the time.

on most light private aircraft just how critical is the weight anyway?
do you think it might be a solution in search of a problem?
Stealth Pilot


In a truly integrated aircraft, the air data computer would sense the 'levelness' of the aircraft and factor out any
gust accelerations. The computer should be able to derive the weight fairly easily...

"Dan D" wrote in message
...


"Stealth Pilot" wrote in message
...

I've heard a discussion of this and the point made was that the wings
are still flying while parked on the ground. in still air the system
would work but with a breeze, or worse in gusts, the system may never
sense the actual aircraft weight.

the other problem was calibrating the weighing (certifying the thing)
and finding really horizontal ground all the time.

on most light private aircraft just how critical is the weight anyway?
do you think it might be a solution in search of a problem?
Stealth Pilot


In a truly integrated aircraft, the air data computer would sense the
'levelness' of the aircraft and factor out any gust accelerations. The
computer should be able to derive the weight fairly easily...



It is not quite that simple. The system you describe would still not
eliminate the steady state component of the wind.

Peter

Stealth Pilot wrote:
On 14 May 2009 10:37:08 GMT, Michael
wrote:
"The issue is that you need to certify the thing, or you can't use it
for any flight crew annunciations. So, to certify it, you need to be
able to guarantee performance. And, if you can't certify it, you can't
take any credit for it being there. Still a potential safety
improvement, but not nearly as cost effective as beating on the flight
crew and dispatches to make sure they actually put in the real
weight."

I've heard a discussion of this and the point made was that the wings
are still flying while parked on the ground. in still air the system
would work but with a breeze, or worse in gusts, the system may never
sense the actual aircraft weight.

So the system could incorporate signals from strain gauges(gages?)
attached to the wings and rudder. Then those forces could be included in
the computation. A nice side benefit of such instrumentation is that one
can view and have recorded a history of the forces on the aircraft during
flights. All your landings where you had a nice squeaker (or dropped it
in) precisely quantified and forever preserved, if you so desire! :-)

the other problem was calibrating the weighing (certifying the thing)
and finding really horizontal ground all the time.

Could also incorporate a signal from a gravity attitude sensor (e.g.
damped plumb bob). Can't think of any useful side benefit to that extra
sensor, though.

on most light private aircraft just how critical is the weight anyway?

C.G. is the useful thing on all size aircraft.

do you think it might be a solution in search of a problem?

Some homebuilders are putting $10k++ instrument panels in their
experimentals that are often expensive solutions in seach of problems, so
I don't see any problem at all in experimental minded builders playing
around in such an underlooked area. Compared to experimenting with things
like engines, attaching sensors is a relatively benign area to experiment
in. (Not entirely benign of course - e.g. one could badly place sensor
wire runs that interfere with controls.)

"JL" == Jim Logajan writes:

JL Could also incorporate a signal from a gravity attitude sensor
JL (e.g. damped plumb bob). Can't think of any useful side
JL benefit to that extra sensor, though.

Good grief. Just average the landing gear weight data over 10 seconds
or so.

--
Almost all absurdity of conduct arises from the imitation of those
whom we cannot resemble.
~ Samuel Johnson

Bob Fry wrote:
"JL" == Jim Logajan writes:

JL Could also incorporate a signal from a gravity attitude sensor
JL (e.g. damped plumb bob). Can't think of any useful side
JL benefit to that extra sensor, though.

Good grief. Just average the landing gear weight data over 10 seconds
or so.


Nope.

You could have a very accurate wrong answer...

"cl" == cavelamb writes:

cl Bob Fry wrote:
"JL" == Jim Logajan writes:
JL Could also incorporate a signal from a gravity attitude
sensor
JL (e.g. damped plumb bob). Can't think of any useful side
JL benefit to that extra sensor, though.
Good grief. Just average the landing gear weight data over 10
seconds or so.


cl Nope.

cl You could have a very accurate wrong answer...

Why?

--
If it were all so simple! If only there were evil people somewhere
insidiously committing evil deeds, and it were necessary only to
separate them from the rest of us and destroy them; but the line
dividing good and evil cuts through the heart of every human
being. And who is willing to destroy a piece of his own heart?
~ Aleksandr Solzhenitsyn

Bob Fry wrote:
"cl" == cavelamb writes:

cl Bob Fry wrote:
"JL" == Jim Logajan writes:
JL Could also incorporate a signal from a gravity attitude
sensor
JL (e.g. damped plumb bob). Can't think of any useful side
JL benefit to that extra sensor, though.
Good grief. Just average the landing gear weight data over 10
seconds or so.


cl Nope.

cl You could have a very accurate wrong answer...

Why?


ALWAYS, Always, I tell you my son...

close the hanger doors before weighing.