The International Cessna^® 170 Association

Would someone who has installed the B.A.S. seat belt/shoulder harnesses post what arm you used to calculate the new weight and balance? I know it's likely there somewhere in the forum, but I couldn't find it with the search function.

Thanks so much.

Bob,
I looked up the Revised Weight & Balance work sheet (Jan, 2000) from when I added B.A.S. Shoulder Harness and I used 64".

Hi Bob,

Mine was slightly different than Johns as follows:

Weight 2.5
Arm 66
Moment 165.0

Airplane is a 1952 B model.

Regards,

Perfect!

Thanks so much.

Bob,
I assumed we were talking about the BAS inertial reel shoulder harness system.

Copied below is the page of instructions covering amoung othe things Weight & Balance. You will note that it says to measure from the datum to the front edge of the trim plate, now being the lazy toad that I am I did not measure from the datum. I instead knew that I installed the inertial reel in front of the "Spar - Assembly Fuselage Rear" so I made my calculations from there. The "Spar - Assembly Fuselage Rear" is according to my 170 Illustrated Part Catalog page 47 item 24- located at Station 65.33", so I took the location of the trim plate (1.33") in front of the "Spar - Assembly Rear" and subtracted that number from the location of the "Spar - Assembly Rear" and concluded that the Station for the new Reel was at 64" aft of datum.


BAS-Inc.
Revision E
1 June, 1995
13. Aircraft with plastic headliners need an additional plastic fairing to fair the reel and dress plate "PN-3" into the molded plastic headliner (see Photo Sheets).
You should have received two (2) each off-white plastic parts and two (2) each clear throw-away plastic parts.
Start by loosening the AN525-10R9 rear dress plate screw so that the plastic fairing can slip under the dress plate. Using one of the clear throw-away parts, trim it to the approximate contour of your headliner so that it will fit between the dress plate and the headliner.
NOTE: The clear plastic part is thin and easy to trim with household type scissors. Try to trim this part to fit between dress plate and the headliner. When properly trimmed, the edge should just touch the headliner. If you have trimmed too far, take a piece of the plastic that you trimmed off, or a piece of thin cardboard, and cut, fit and tape into place. this technique also works when trimming around skylight trim moldings (see photos).
When you are happy with the fit, remove the part and lay it on the outside of one of the white plastic parts, align and trace edge with a pencil. Cut on line and install finished part.
--NOTE: because the white plastic is thicker, a small amount of finish trimming may be needed.
CAUTION: DO NOT FORGET TO TIGHTEN THE REAR DRESS PLATE SCREWS AFTER THE FINISHED FAIRINGS ARE INSTALLED.
14. Check the inertia reel's operation. Note there are several ways to do this without crashing the airplane! Remove greasy fingerprints from the upholstery.
15. Fill out the aircraft logs and an FAA form 337.


16. In revising weight and balance data for the aircraft, note that the B.A.S., Inc. system weighs 5 pounds, plus or minus an ounce or two, depending on your aircraft model. Just subtract the weight of the restraint system removed from the 5-pound weight of the new system. Then measure from the datum to the front edge of the dress plate (PN-3) to get the "arm". (WEIGHT X ARM = MOMENT)


NOTE:
If you experience problems, or if the instructions are not clear to you, please phone B.A.S., Inc. at (360) 832-6566 before proceeding. If we are not available when you call, let the phone ring -- our answering machine will take the message and we will contact you promptly.