From IAC Tech Manual Vol II:
We then ran the same tests on the ACRO SPORT
N1AC. It has slightly different geometry, longer wires,
etc. This is what we came up with for the Aero Sport
and the Super Aero Sport recommendations. (Use a 50
lb. pull at the wire midpoint; use a rope loop. Do not use
wire or sharp objects around the tie rods.) What we used
were two 27 lb. fish scales in parallel. We pull them to
25 lbs. each to give a total pull of 50 lbs. These fishing
fisherman's "De-liar" are available in many fishing
supply houses.
Tie Rod Location DEFLECTION at 50 lbs.
Front Flying Wires 1 3/4"
Rear Flying Wires 1 3/8"
Landing Wires 1 1/4"
Tail Wires - Upper 1 3/4"
Tail Wires -Lower 1 1/4"
Roll Wires 3/8 "
For the engineering minded, we have a friend who
has an old World War II flying wire tensiometer. The
flying and landing wires measured a 750 lb. tension
at the above deflection. This corresponds to a "dull
thud". It is felt that the deflection method is a very
good method in getting the correct tension on Aero
Sport, Pitts and other aircraft. You may have to work
out the geometry for tensions on your own individual
aircraft. It might be mentioned that obtaining a tensiometer
of the proper tension for flying wires is very
difficult in this day and age. It is unnecessary if one does
use the above method of deflection.
We then ran the same tests on the ACRO SPORT
N1AC. It has slightly different geometry, longer wires,
etc. This is what we came up with for the Aero Sport
and the Super Aero Sport recommendations. (Use a 50
lb. pull at the wire midpoint; use a rope loop. Do not use
wire or sharp objects around the tie rods.) What we used
were two 27 lb. fish scales in parallel. We pull them to
25 lbs. each to give a total pull of 50 lbs. These fishing
fisherman's "De-liar" are available in many fishing
supply houses.
Tie Rod Location DEFLECTION at 50 lbs.
Front Flying Wires 1 3/4"
Rear Flying Wires 1 3/8"
Landing Wires 1 1/4"
Tail Wires - Upper 1 3/4"
Tail Wires -Lower 1 1/4"
Roll Wires 3/8 "
For the engineering minded, we have a friend who
has an old World War II flying wire tensiometer. The
flying and landing wires measured a 750 lb. tension
at the above deflection. This corresponds to a "dull
thud". It is felt that the deflection method is a very
good method in getting the correct tension on Aero
Sport, Pitts and other aircraft. You may have to work
out the geometry for tensions on your own individual
aircraft. It might be mentioned that obtaining a tensiometer
of the proper tension for flying wires is very
difficult in this day and age. It is unnecessary if one does
use the above method of deflection.
