Since we're talking electronic sensors...

On 14 May, 11:37, Michael wrote:
On Wed, 13 May 2009 15:10:26 -0500, Jim Logajan wrote:
Honeywell has such a system for big aircraft:

http://www.honeywell.com/sites/aero/...rs3_C91E0E6C1-

A71D-06B3-97EC-617A9F35BEC1_H33815F58-00F1-0786-C716-E0431B6C7F21.htm



Honeywell advert on this link (contains embedded PDF):
http://www.flightglobal.com/pdfarchi...0-%200862.html

A twenty-two year old advert

Some Googling has turned up another system that was used on 707s called
STAN, which stood for "Sum Total and Nose". It was reported to work well.

I'm not surprised that this has been done but it obviously hasn't caught
on and that is surprising.
This was discussed somewhere where quite a few active
airline pilots hang out and they were most unimpressed by
the concept. One issue raised was they they did not really
want to know what the all up weight actually was. Or at least the
management didn't want to have to own up. That's what they
said anyway.

The technology is for sure used in aviation - engine torque
sensor for example will use strain gauge I would think.

I've made a toy one and it is all quite easy but a certifiable one
is clearly another matter altogether.

bod43 wrote:
On 14 May, 11:37, Michael wrote:
On Wed, 13 May 2009 15:10:26 -0500, Jim Logajan wrote:
Honeywell has such a system for big aircraft:
http://www.honeywell.com/sites/aero/...rs3_C91E0E6C1-
A71D-06B3-97EC-617A9F35BEC1_H33815F58-00F1-0786-C716-E0431B6C7F21.htm



Honeywell advert on this link (contains embedded PDF):
http://www.flightglobal.com/pdfarchi...0-%200862.html
A twenty-two year old advert

Some Googling has turned up another system that was used on 707s called
STAN, which stood for "Sum Total and Nose". It was reported to work well.

I'm not surprised that this has been done but it obviously hasn't caught
on and that is surprising.
This was discussed somewhere where quite a few active
airline pilots hang out and they were most unimpressed by
the concept. One issue raised was they they did not really
want to know what the all up weight actually was. Or at least the
management didn't want to have to own up. That's what they
said anyway.

The technology is for sure used in aviation - engine torque
sensor for example will use strain gauge I would think.

I've made a toy one and it is all quite easy but a certifiable one
is clearly another matter altogether.


I can't speak for all aircraft but some use oil pressure for
measuring torque. For the life of me I can't recall how it's done, I
just remember changing a torque transmitter on a T-29 in 1975. There was
a port on the front of the crank case near the shaft. A capillary tube
lead from there to the transmitter a few feet back.

Dan, U.S. Air Force, retired