Cooper-Travers Hawk

June 2003 35
■ Dave Linstrum
To launch the Hawk, release propeller tip first,
then let the model fly gently from your hand.
Do not throw!
DEDICATED SCALE enthusiasts often go to great lengths to find obscure full-scale
aircraft to model. They delight in finding something that few fliers have ever heard of,
much less modeled. They spend hours in libraries or on the Internet looking for that
obscure subject that will be the envy of their peers.
I found a complete illustrated dossier on the Cooper-Travers Hawk by accident. I
was in Los Angeles, California (I live in Orlando, Florida), visiting my daughter who
lives in Beverly Hills. I was driving along an urban street and came upon a roadside
newsstand that appeared to have a broad selection of periodicals. I immediately
spotted the July 2001 Aeroplane Monthly—a venerable British publication that
usually has the latest news on aircraft and often has detailed historical articles.
This issue had a gem: a fully illustrated (photos and detailed three-view)
presentation of the 1924 Cooper-Travers Hawk. When I saw the query note by Editor
Michael Oakey, I was hooked! He stated: “It represents a challenging subject for the
aeromodellers among our readership—who will be the first to produce a flying scale
model?”
Thus challenged, I sketched out the model you see here on an SWA barf bag at
35,000 feet shortly after leaving the Los Angeles International Airport. When I got
home, I sent Editor Oakey (himself an aeromodeler) my terse E-mail reply—even
before I glued the first sticks of my FAC (Flying Aces Club) Profile No-Cal Scale
design. I wrote: “A Yank will be first!” He sent his E-mail reply
from London that he was looking forward to hearing more.
I built the model, took flight photos, and mailed them to him as
proof. Indeed, I was first.
In the article “Lesser-Known Aircraft” by distinguished aerohistorian
Arthur W.J.G. Ord-Hume, there is a photo of casual,
intrepid test pilot James L. Travers taken when he was a regular
flier at Hendon Aerodrome (London) in 1912. There is also a
photo of Lt. Col. Jim Travers on approach at Croydon Aerodrome
(London) taken the afternoon of February 14, 1924, captioned:
“ … The aircraft and its designer are seconds from disaster.
The picture shows clearly the extremely deep undercambered
Gottingen wing section, as well as revealing the five-degree angle
of incidence on the unbraced tailplane.”
My ink sketch from that photo shows these two fatal design
flaws. The thick wing was to accommodate two passengers in the
wing root—one on either side of the pilot’s cockpit. Cooper put
the positive incidence in the tailplane, and it gave Travers pause
before he took off, but not enough pause …
A fatal crash on the first test flight was proof enough for me to
eliminate both of those flaws from my model design. I used a
simple undercambered wing rib and set the stabilizer at 0°—a
setup proven on my past No-Cal designs (such as the Dornier
Falke) as stable for Free Flight. I was proven right—and no test
pilot was put at risk.
As Aeroplane stated, “The short life of the one-off Cooper-
Travers Hawk of 1924 has denied it a place in aviation history.
Arthur W.J.G. Ord-Hume investigates why this revolutionary
design ended in a flaming pyre.”
You do not need further history to build this simple replica, but
you can order a back issue of the 7/01 Aeroplane if you want more
details or want to design your own Radio Control version. See the
end of this article for details. I thank that publication and Editor
Oakey for his kind permission to reproduce here the beautifully
drawn Giuseppe Picarella three-view and the preceding quotes.
Giuseppe is a maestro.
CONSTRUCTION
Preparation: Make photocopies (two each—the second set is for
patterns) of the two letter-size plates of building plans. This way
36 MODEL AVIATION
you can avoid cutting up your Model
Aviation. Be sure to hold the magazine
down tight on the copier glass to capture
the image near the binding.
Tape the building plates together along
match line A-B with 3M Scotch Magic
Tape. Tape the plates to your building
board (an 11 x 17-inch scrap of pinstickable
Fome-Cor will do), and cover
with waxed paper to prevent glued balsa
from adhering to the plans.
Materials and Tools: Free Flight stickand-
tissue construction and flying require
special tools and materials. At the least,
you must have an X-Acto (or similar)
model knife with a #11 pointed blade,
bead-head dressmaker pins, a self-healing
cutting board (or a scrap of dark artist’s
matboard), glue (use Duco cement or thickgel
CyA [cyanoacrylate]), a glue stick for
covering with tissue, and needle-nose pliers
for bending the rear hook and propeller
shaft.
Get the preceding items at your local
Wal-Mart. You may need to go to an art
store for the cutting/matboard. Cutting balsa on this is a pleasure.
Do not cut on the plans!
Type: FF FAC Profile No-Cal Scale
Wingspan: 16 inches
Power: 11- to 12-inch loop FAI Tan
II Rubber
Flying weight: 8-10 grams
Construction: Balsa sheet and strip
Covering/finish: Yellow or beige
tissue, Krylon Espresso aerosol
Notice that only one side of the Hawk’s profile fuselage is
covered. This saves weight and keeps the project simple.
Photograph it from the opposite side!
Photos by the author Graphic Design by Carla Kunz
June 2003 37
Few parts make for rapid building, even with the curved tips. All of the parts are shown,
pinned down for drying on the plans. This is a fun project.
Use artist’s matboard or 1⁄16 balsa for templates to form the fin, wingtips, and stabilizer.
Form these parts from wetted 1⁄32 strips.
Most hobby shops do not have the
light balsa and tissue needed to build this
model. An excellent mail-order source is
Peck-Polymers (see the company’s ad in
Model Aviation). To order the complete
catalog for $4, which is a good
investment, call (619) 448-1818. Mail
order is a great resource. Peck is the best
for Free Flight.
You should order 1⁄16 and 1⁄32 balsa
(get small sheets and a dozen 1⁄16 square
sticks), 1⁄32 plywood, a sheet of yellow or
tan Esaki tissue, a 4-inch black square-tip
plastic propeller, a pack of 1⁄32-inchdiameter
shafts, a pack of white nylon
Peanut bearings, a pack of 1-inch black
plastic wheels (unless you want to cut
your own from white carryout tray foam),
a pack of 1⁄8-inch FAI Tan II rubber, a
Peck 5:1 winder for rubber, and the XActo.
Good books to have are Don Ross’s
Rubber Power Flying Models and
Building the Peck ROG by Bill Warner.
Both have many photos and excellent
drawings by Jim Kaman. They will be
treasured in your modeling library. Both
are available from Peck-Polymers.
If you have no stick-and-tissue
experience, order some simple kits: an
AMA Cub (Delta Dart), a Peck ROG, and
perhaps a Sky Bunny. These have
complete, illustrated instructions that will
make you skillful in a hurry. The Hawk is
not a beginner’s model!
Building: I will not tell you how to glue
Part A to Part B; the aforementioned kits
and books will teach you that. The simple
Cooper-Travers Hawk is not an ARF
(Almost Ready-to Fly) with an instruction
book; it is a craftsman’s project requiring
some basic skills.
The sliced wing ribs may be new to
you. Make a rib-slicing pattern from 1⁄32
plywood using the extra plans copy (gluestick
the pattern to the plywood). Cut a
sheet of 1⁄16 balsa to the length of the
center rib, then tape it to the cutting board
at the bottom of the balsa. Slice away
with the X-Acto knife at the top and
discard the scrap, then move the pattern
down 1⁄16 inch. Carefully slice again; you
may need a couple of light strokes.
Cut a full set of ribs. Taper them from
the rear before you glue them in place to
the leading edge and trailing edge. Note
that there is only one center rib, which is
added as you put in the 1-inch dihedral.
Be sure that half of the wing is pinned
down flat as you raise the other tip.
Another unusual method is the wet
lamination of balsa for the round-corner
tips, aileron ends, and fin/rudder. This
requires making forms from artists’
matboard or 1⁄16 balsa; see the photo.
Using the extra “patterns” photocopy
of the plans, glue-stick the tips (one on
each wing and stabilizer) and fin/rudder
to the pattern material. Cut to the inside
line of the double lines of the curved part.
Allow some extra (straight) beyond the
end of the curve; this is for taping the
lamination to the form.
The lamination will be two strips of 1⁄32 x
1⁄16 that appear 1⁄16-inch wide on the plans to
match the 1⁄16 square sticks. Lightly sand the
edges of the patterns and wax them to
prevent glue from sticking the part to the
form.
Cut the strips to length a bit longer than
the form edge, and soak them in hot water
in a saucer. Two at a time, blot excess water
with a paper napkin. Apply a bead of
Titebond or Elmer’s carpenter’s glue to one
strip, then stack the other on top of it,
wiping away any glue that leaks out the
edge. Your lamination is ready to bend
around the form.
Cut two small pieces of 3M Scotch
Magic Tape to hold down the ends. Affix
one end of the strips to the form, pull firmly
and tight to form around the curve, then
affix the other end. Now you are ready for
the fun part.
Put a coffee mug upside down in the
microwave and set the wet part/form atop it.
Microwave for one minute on high, and
presto! You have a permanently curved part
that only needs cutting loose from the form
at the ends. Cut to the line you see at the
end of “straight” for exact length. Discard
the excess with tape. Repeat until you have
all parts; the stabilizer and wingtip/aileron
forms get used twice.
This is the easy way to make curves on a
Finished parts ready for assembly. Black propeller is smallest North Pacific/Peck size.
You can clearly see the undercambered rib strips. The wheels are made from 1⁄16 sheet
foam with silver paper hubs.
38 MODEL AVIATION
stick-and-tissue model—and it’s much
easier than cutting segments of curves from
1⁄16 balsa sheet and piecing them together.
This is how they did it in the 1930s, but
they did not have such water-based glues or
microwaves then. Technology can make
building faster and better.
Assembly and Painting: After parts are
covered with tissue (use the glue stick on
balsa, then pat the tissue down and trim),
mask off the ailerons, rudder, and elevator
with low-tack masking tape and paper. If
you do not want an accurate color, simply
use the colored tissue. Note that the flying
surfaces are covered on the top only and the
body/fin left side only.
Get a can of Krylon Short Cuts acrylic
aerosol in Espresso (color SCS-035). It will
give your tissue a coffeelike tone—similar
to aged shellac on 1924 aircraft fabric.
Carefully mist a light coat on the exposed
tissue and let it dry before unmasking. Paint
the nose with aluminum acrylic paint from
Wal-Mart.
Attach the rear hook and bearing to the
motorstick (see details on plans), then glue
to the right side of the body as shown on
the plans. Attach the stabilizer, then attach
the fin to the body. Tilt the right side of
the stabilizer up slightly, as seen from the
rear; this will induce a natural right-turn
circle.
Attach the wing to the top of the body;
you may want to pin it at the leading edge
and trailing edge while the Duco dries.
Check to make sure that it is level.
Attach the splayed 1⁄32 plywood landinggear
struts and add the wheels, which can
be glued on. Rotating wheels are not
required; this model is hand launched only.
Add the 1⁄32 plywood rear skid.
Make a rubber motor in approximately a
12-inch loop, tying the ends in a square
knot. Lubricate the motor with Johnson’s
Baby Shampoo and wipe off the excess.
Hang the motor from the shaft and the
rear hook, then wind in a few hand turns,
rotating the propeller clockwise while
holding the nose. Let the propeller breeze
blow in your face—it’s cool!
Check the balance (see plans) with the
motor installed. If necessary, add clay to
the nose in the sheeted section. Correct
balance is essential for Free Flight—or for
any aircraft, piloted or not.
Go to a copy shop and ask for a
discarded box used to ship letter-size copy
paper. Do not use grocery-store boxes; the
lids implode. Put your model in your
storage/transport box, but don’t put any
heavy objects in there with it—a rolling
winder could damage the model.
Flying: It is pointless to test-glide such a
small model. If you fly outdoors (it is
okay to fly in a school gym if it is windy
outdoors), hand wind roughly 200 turns
into the motor and launch the model
straight and level into the wind (10 mph
or less). Do not throw the model!
Your Hawk should fly in a loose right
circle, climbing slightly. Adjust it by
bending the nose bearing to the right for
right thrust and bending the right aileron
down by cracking the tip ribs slightly and
gluing them. This will keep the wing up
(like an aileron) in a turn.
Progress to stretch-winding with the
Peck winder. You will need a flying
buddy to hold the model (upside-down)
by the nose bearing/propeller hub while
you attach the winder and stretch the
motor out approximately twice its length
to the rear.
Put in roughly 100 winder turns while
coming in, then remove the motor from
the winder and attach it to the rear hook.
Take the model from your buddy (give
him/her the winder), and gently launch it.
It should climb out in a loose right circle.
I hope you enjoyed the aviation history
and building this replica of an ill-fated
aircraft. Good luck with your Cooper-
Travers Hawk. Happy landings!
For an issue of the 7/01 Aeroplane
Monthly, send an airmail letter to the
Circulation Department, Aeroplane
Monthly, King’s Reach Tower, Stamford
St., London SE19LS, England.
The cover price is 3.20 pounds, but the
back-issue price plus postage would be in
euros. The easiest way to pay is by major
credit card so there is no trouble with
exchange rates. Include your name as it is
printed on the card, the card’s expiration
date, and the name of the card. That will
expedite your order.
You may order a copy by inquiring by
E-mail to [email protected] or
[email protected]. MA
Dave Linstrum
4016 Maguire Blvd. Apt. 3314
Orlando FL 32803
June 2003 39
Test pilot Lt. Col. Jim Travers flies Cooper-Travers Hawk on approach at Croydon (original London airport) on February 14,
1924, just seconds before fatal crash on first flight. Extremely deep undercambered Gottingen airfoil and 5° positive
incidence on tailplane were likely causes for crash. Ink sketch by author is from photo by Cecil Arthur Rae, who was later a
test pilot for British aircraft manufacturer Boulton Paul.

June 2003 35
■ Dave Linstrum
To launch the Hawk, release propeller tip first,
then let the model fly gently from your hand.
Do not throw!
DEDICATED SCALE enthusiasts often go to great lengths to find obscure full-scale
aircraft to model. They delight in finding something that few fliers have ever heard of,
much less modeled. They spend hours in libraries or on the Internet looking for that
obscure subject that will be the envy of their peers.
I found a complete illustrated dossier on the Cooper-Travers Hawk by accident. I
was in Los Angeles, California (I live in Orlando, Florida), visiting my daughter who
lives in Beverly Hills. I was driving along an urban street and came upon a roadside
newsstand that appeared to have a broad selection of periodicals. I immediately
spotted the July 2001 Aeroplane Monthly—a venerable British publication that
usually has the latest news on aircraft and often has detailed historical articles.
This issue had a gem: a fully illustrated (photos and detailed three-view)
presentation of the 1924 Cooper-Travers Hawk. When I saw the query note by Editor
Michael Oakey, I was hooked! He stated: “It represents a challenging subject for the
aeromodellers among our readership—who will be the first to produce a flying scale
model?”
Thus challenged, I sketched out the model you see here on an SWA barf bag at
35,000 feet shortly after leaving the Los Angeles International Airport. When I got
home, I sent Editor Oakey (himself an aeromodeler) my terse E-mail reply—even
before I glued the first sticks of my FAC (Flying Aces Club) Profile No-Cal Scale
design. I wrote: “A Yank will be first!” He sent his E-mail reply
from London that he was looking forward to hearing more.
I built the model, took flight photos, and mailed them to him as
proof. Indeed, I was first.
In the article “Lesser-Known Aircraft” by distinguished aerohistorian
Arthur W.J.G. Ord-Hume, there is a photo of casual,
intrepid test pilot James L. Travers taken when he was a regular
flier at Hendon Aerodrome (London) in 1912. There is also a
photo of Lt. Col. Jim Travers on approach at Croydon Aerodrome
(London) taken the afternoon of February 14, 1924, captioned:
“ … The aircraft and its designer are seconds from disaster.
The picture shows clearly the extremely deep undercambered
Gottingen wing section, as well as revealing the five-degree angle
of incidence on the unbraced tailplane.”
My ink sketch from that photo shows these two fatal design
flaws. The thick wing was to accommodate two passengers in the
wing root—one on either side of the pilot’s cockpit. Cooper put
the positive incidence in the tailplane, and it gave Travers pause
before he took off, but not enough pause …
A fatal crash on the first test flight was proof enough for me to
eliminate both of those flaws from my model design. I used a
simple undercambered wing rib and set the stabilizer at 0°—a
setup proven on my past No-Cal designs (such as the Dornier
Falke) as stable for Free Flight. I was proven right—and no test
pilot was put at risk.
As Aeroplane stated, “The short life of the one-off Cooper-
Travers Hawk of 1924 has denied it a place in aviation history.
Arthur W.J.G. Ord-Hume investigates why this revolutionary
design ended in a flaming pyre.”
You do not need further history to build this simple replica, but
you can order a back issue of the 7/01 Aeroplane if you want more
details or want to design your own Radio Control version. See the
end of this article for details. I thank that publication and Editor
Oakey for his kind permission to reproduce here the beautifully
drawn Giuseppe Picarella three-view and the preceding quotes.
Giuseppe is a maestro.
CONSTRUCTION
Preparation: Make photocopies (two each—the second set is for
patterns) of the two letter-size plates of building plans. This way
36 MODEL AVIATION
you can avoid cutting up your Model
Aviation. Be sure to hold the magazine
down tight on the copier glass to capture
the image near the binding.
Tape the building plates together along
match line A-B with 3M Scotch Magic
Tape. Tape the plates to your building
board (an 11 x 17-inch scrap of pinstickable
Fome-Cor will do), and cover
with waxed paper to prevent glued balsa
from adhering to the plans.
Materials and Tools: Free Flight stickand-
tissue construction and flying require
special tools and materials. At the least,
you must have an X-Acto (or similar)
model knife with a #11 pointed blade,
bead-head dressmaker pins, a self-healing
cutting board (or a scrap of dark artist’s
matboard), glue (use Duco cement or thickgel
CyA [cyanoacrylate]), a glue stick for
covering with tissue, and needle-nose pliers
for bending the rear hook and propeller
shaft.
Get the preceding items at your local
Wal-Mart. You may need to go to an art
store for the cutting/matboard. Cutting balsa on this is a pleasure.
Do not cut on the plans!
Type: FF FAC Profile No-Cal Scale
Wingspan: 16 inches
Power: 11- to 12-inch loop FAI Tan
II Rubber
Flying weight: 8-10 grams
Construction: Balsa sheet and strip
Covering/finish: Yellow or beige
tissue, Krylon Espresso aerosol
Notice that only one side of the Hawk’s profile fuselage is
covered. This saves weight and keeps the project simple.
Photograph it from the opposite side!
Photos by the author Graphic Design by Carla Kunz
June 2003 37
Few parts make for rapid building, even with the curved tips. All of the parts are shown,
pinned down for drying on the plans. This is a fun project.
Use artist’s matboard or 1⁄16 balsa for templates to form the fin, wingtips, and stabilizer.
Form these parts from wetted 1⁄32 strips.
Most hobby shops do not have the
light balsa and tissue needed to build this
model. An excellent mail-order source is
Peck-Polymers (see the company’s ad in
Model Aviation). To order the complete
catalog for $4, which is a good
investment, call (619) 448-1818. Mail
order is a great resource. Peck is the best
for Free Flight.
You should order 1⁄16 and 1⁄32 balsa
(get small sheets and a dozen 1⁄16 square
sticks), 1⁄32 plywood, a sheet of yellow or
tan Esaki tissue, a 4-inch black square-tip
plastic propeller, a pack of 1⁄32-inchdiameter
shafts, a pack of white nylon
Peanut bearings, a pack of 1-inch black
plastic wheels (unless you want to cut
your own from white carryout tray foam),
a pack of 1⁄8-inch FAI Tan II rubber, a
Peck 5:1 winder for rubber, and the XActo.
Good books to have are Don Ross’s
Rubber Power Flying Models and
Building the Peck ROG by Bill Warner.
Both have many photos and excellent
drawings by Jim Kaman. They will be
treasured in your modeling library. Both
are available from Peck-Polymers.
If you have no stick-and-tissue
experience, order some simple kits: an
AMA Cub (Delta Dart), a Peck ROG, and
perhaps a Sky Bunny. These have
complete, illustrated instructions that will
make you skillful in a hurry. The Hawk is
not a beginner’s model!
Building: I will not tell you how to glue
Part A to Part B; the aforementioned kits
and books will teach you that. The simple
Cooper-Travers Hawk is not an ARF
(Almost Ready-to Fly) with an instruction
book; it is a craftsman’s project requiring
some basic skills.
The sliced wing ribs may be new to
you. Make a rib-slicing pattern from 1⁄32
plywood using the extra plans copy (gluestick
the pattern to the plywood). Cut a
sheet of 1⁄16 balsa to the length of the
center rib, then tape it to the cutting board
at the bottom of the balsa. Slice away
with the X-Acto knife at the top and
discard the scrap, then move the pattern
down 1⁄16 inch. Carefully slice again; you
may need a couple of light strokes.
Cut a full set of ribs. Taper them from
the rear before you glue them in place to
the leading edge and trailing edge. Note
that there is only one center rib, which is
added as you put in the 1-inch dihedral.
Be sure that half of the wing is pinned
down flat as you raise the other tip.
Another unusual method is the wet
lamination of balsa for the round-corner
tips, aileron ends, and fin/rudder. This
requires making forms from artists’
matboard or 1⁄16 balsa; see the photo.
Using the extra “patterns” photocopy
of the plans, glue-stick the tips (one on
each wing and stabilizer) and fin/rudder
to the pattern material. Cut to the inside
line of the double lines of the curved part.
Allow some extra (straight) beyond the
end of the curve; this is for taping the
lamination to the form.
The lamination will be two strips of 1⁄32 x
1⁄16 that appear 1⁄16-inch wide on the plans to
match the 1⁄16 square sticks. Lightly sand the
edges of the patterns and wax them to
prevent glue from sticking the part to the
form.
Cut the strips to length a bit longer than
the form edge, and soak them in hot water
in a saucer. Two at a time, blot excess water
with a paper napkin. Apply a bead of
Titebond or Elmer’s carpenter’s glue to one
strip, then stack the other on top of it,
wiping away any glue that leaks out the
edge. Your lamination is ready to bend
around the form.
Cut two small pieces of 3M Scotch
Magic Tape to hold down the ends. Affix
one end of the strips to the form, pull firmly
and tight to form around the curve, then
affix the other end. Now you are ready for
the fun part.
Put a coffee mug upside down in the
microwave and set the wet part/form atop it.
Microwave for one minute on high, and
presto! You have a permanently curved part
that only needs cutting loose from the form
at the ends. Cut to the line you see at the
end of “straight” for exact length. Discard
the excess with tape. Repeat until you have
all parts; the stabilizer and wingtip/aileron
forms get used twice.
This is the easy way to make curves on a
Finished parts ready for assembly. Black propeller is smallest North Pacific/Peck size.
You can clearly see the undercambered rib strips. The wheels are made from 1⁄16 sheet
foam with silver paper hubs.
38 MODEL AVIATION
stick-and-tissue model—and it’s much
easier than cutting segments of curves from
1⁄16 balsa sheet and piecing them together.
This is how they did it in the 1930s, but
they did not have such water-based glues or
microwaves then. Technology can make
building faster and better.
Assembly and Painting: After parts are
covered with tissue (use the glue stick on
balsa, then pat the tissue down and trim),
mask off the ailerons, rudder, and elevator
with low-tack masking tape and paper. If
you do not want an accurate color, simply
use the colored tissue. Note that the flying
surfaces are covered on the top only and the
body/fin left side only.
Get a can of Krylon Short Cuts acrylic
aerosol in Espresso (color SCS-035). It will
give your tissue a coffeelike tone—similar
to aged shellac on 1924 aircraft fabric.
Carefully mist a light coat on the exposed
tissue and let it dry before unmasking. Paint
the nose with aluminum acrylic paint from
Wal-Mart.
Attach the rear hook and bearing to the
motorstick (see details on plans), then glue
to the right side of the body as shown on
the plans. Attach the stabilizer, then attach
the fin to the body. Tilt the right side of
the stabilizer up slightly, as seen from the
rear; this will induce a natural right-turn
circle.
Attach the wing to the top of the body;
you may want to pin it at the leading edge
and trailing edge while the Duco dries.
Check to make sure that it is level.
Attach the splayed 1⁄32 plywood landinggear
struts and add the wheels, which can
be glued on. Rotating wheels are not
required; this model is hand launched only.
Add the 1⁄32 plywood rear skid.
Make a rubber motor in approximately a
12-inch loop, tying the ends in a square
knot. Lubricate the motor with Johnson’s
Baby Shampoo and wipe off the excess.
Hang the motor from the shaft and the
rear hook, then wind in a few hand turns,
rotating the propeller clockwise while
holding the nose. Let the propeller breeze
blow in your face—it’s cool!
Check the balance (see plans) with the
motor installed. If necessary, add clay to
the nose in the sheeted section. Correct
balance is essential for Free Flight—or for
any aircraft, piloted or not.
Go to a copy shop and ask for a
discarded box used to ship letter-size copy
paper. Do not use grocery-store boxes; the
lids implode. Put your model in your
storage/transport box, but don’t put any
heavy objects in there with it—a rolling
winder could damage the model.
Flying: It is pointless to test-glide such a
small model. If you fly outdoors (it is
okay to fly in a school gym if it is windy
outdoors), hand wind roughly 200 turns
into the motor and launch the model
straight and level into the wind (10 mph
or less). Do not throw the model!
Your Hawk should fly in a loose right
circle, climbing slightly. Adjust it by
bending the nose bearing to the right for
right thrust and bending the right aileron
down by cracking the tip ribs slightly and
gluing them. This will keep the wing up
(like an aileron) in a turn.
Progress to stretch-winding with the
Peck winder. You will need a flying
buddy to hold the model (upside-down)
by the nose bearing/propeller hub while
you attach the winder and stretch the
motor out approximately twice its length
to the rear.
Put in roughly 100 winder turns while
coming in, then remove the motor from
the winder and attach it to the rear hook.
Take the model from your buddy (give
him/her the winder), and gently launch it.
It should climb out in a loose right circle.
I hope you enjoyed the aviation history
and building this replica of an ill-fated
aircraft. Good luck with your Cooper-
Travers Hawk. Happy landings!
For an issue of the 7/01 Aeroplane
Monthly, send an airmail letter to the
Circulation Department, Aeroplane
Monthly, King’s Reach Tower, Stamford
St., London SE19LS, England.
The cover price is 3.20 pounds, but the
back-issue price plus postage would be in
euros. The easiest way to pay is by major
credit card so there is no trouble with
exchange rates. Include your name as it is
printed on the card, the card’s expiration
date, and the name of the card. That will
expedite your order.
You may order a copy by inquiring by
E-mail to [email protected] or
[email protected]. MA
Dave Linstrum
4016 Maguire Blvd. Apt. 3314
Orlando FL 32803
June 2003 39
Test pilot Lt. Col. Jim Travers flies Cooper-Travers Hawk on approach at Croydon (original London airport) on February 14,
1924, just seconds before fatal crash on first flight. Extremely deep undercambered Gottingen airfoil and 5° positive
incidence on tailplane were likely causes for crash. Ink sketch by author is from photo by Cecil Arthur Rae, who was later a
test pilot for British aircraft manufacturer Boulton Paul.

June 2003 35
■ Dave Linstrum
To launch the Hawk, release propeller tip first,
then let the model fly gently from your hand.
Do not throw!
DEDICATED SCALE enthusiasts often go to great lengths to find obscure full-scale
aircraft to model. They delight in finding something that few fliers have ever heard of,
much less modeled. They spend hours in libraries or on the Internet looking for that
obscure subject that will be the envy of their peers.
I found a complete illustrated dossier on the Cooper-Travers Hawk by accident. I
was in Los Angeles, California (I live in Orlando, Florida), visiting my daughter who
lives in Beverly Hills. I was driving along an urban street and came upon a roadside
newsstand that appeared to have a broad selection of periodicals. I immediately
spotted the July 2001 Aeroplane Monthly—a venerable British publication that
usually has the latest news on aircraft and often has detailed historical articles.
This issue had a gem: a fully illustrated (photos and detailed three-view)
presentation of the 1924 Cooper-Travers Hawk. When I saw the query note by Editor
Michael Oakey, I was hooked! He stated: “It represents a challenging subject for the
aeromodellers among our readership—who will be the first to produce a flying scale
model?”
Thus challenged, I sketched out the model you see here on an SWA barf bag at
35,000 feet shortly after leaving the Los Angeles International Airport. When I got
home, I sent Editor Oakey (himself an aeromodeler) my terse E-mail reply—even
before I glued the first sticks of my FAC (Flying Aces Club) Profile No-Cal Scale
design. I wrote: “A Yank will be first!” He sent his E-mail reply
from London that he was looking forward to hearing more.
I built the model, took flight photos, and mailed them to him as
proof. Indeed, I was first.
In the article “Lesser-Known Aircraft” by distinguished aerohistorian
Arthur W.J.G. Ord-Hume, there is a photo of casual,
intrepid test pilot James L. Travers taken when he was a regular
flier at Hendon Aerodrome (London) in 1912. There is also a
photo of Lt. Col. Jim Travers on approach at Croydon Aerodrome
(London) taken the afternoon of February 14, 1924, captioned:
“ … The aircraft and its designer are seconds from disaster.
The picture shows clearly the extremely deep undercambered
Gottingen wing section, as well as revealing the five-degree angle
of incidence on the unbraced tailplane.”
My ink sketch from that photo shows these two fatal design
flaws. The thick wing was to accommodate two passengers in the
wing root—one on either side of the pilot’s cockpit. Cooper put
the positive incidence in the tailplane, and it gave Travers pause
before he took off, but not enough pause …
A fatal crash on the first test flight was proof enough for me to
eliminate both of those flaws from my model design. I used a
simple undercambered wing rib and set the stabilizer at 0°—a
setup proven on my past No-Cal designs (such as the Dornier
Falke) as stable for Free Flight. I was proven right—and no test
pilot was put at risk.
As Aeroplane stated, “The short life of the one-off Cooper-
Travers Hawk of 1924 has denied it a place in aviation history.
Arthur W.J.G. Ord-Hume investigates why this revolutionary
design ended in a flaming pyre.”
You do not need further history to build this simple replica, but
you can order a back issue of the 7/01 Aeroplane if you want more
details or want to design your own Radio Control version. See the
end of this article for details. I thank that publication and Editor
Oakey for his kind permission to reproduce here the beautifully
drawn Giuseppe Picarella three-view and the preceding quotes.
Giuseppe is a maestro.
CONSTRUCTION
Preparation: Make photocopies (two each—the second set is for
patterns) of the two letter-size plates of building plans. This way
36 MODEL AVIATION
you can avoid cutting up your Model
Aviation. Be sure to hold the magazine
down tight on the copier glass to capture
the image near the binding.
Tape the building plates together along
match line A-B with 3M Scotch Magic
Tape. Tape the plates to your building
board (an 11 x 17-inch scrap of pinstickable
Fome-Cor will do), and cover
with waxed paper to prevent glued balsa
from adhering to the plans.
Materials and Tools: Free Flight stickand-
tissue construction and flying require
special tools and materials. At the least,
you must have an X-Acto (or similar)
model knife with a #11 pointed blade,
bead-head dressmaker pins, a self-healing
cutting board (or a scrap of dark artist’s
matboard), glue (use Duco cement or thickgel
CyA [cyanoacrylate]), a glue stick for
covering with tissue, and needle-nose pliers
for bending the rear hook and propeller
shaft.
Get the preceding items at your local
Wal-Mart. You may need to go to an art
store for the cutting/matboard. Cutting balsa on this is a pleasure.
Do not cut on the plans!
Type: FF FAC Profile No-Cal Scale
Wingspan: 16 inches
Power: 11- to 12-inch loop FAI Tan
II Rubber
Flying weight: 8-10 grams
Construction: Balsa sheet and strip
Covering/finish: Yellow or beige
tissue, Krylon Espresso aerosol
Notice that only one side of the Hawk’s profile fuselage is
covered. This saves weight and keeps the project simple.
Photograph it from the opposite side!
Photos by the author Graphic Design by Carla Kunz
June 2003 37
Few parts make for rapid building, even with the curved tips. All of the parts are shown,
pinned down for drying on the plans. This is a fun project.
Use artist’s matboard or 1⁄16 balsa for templates to form the fin, wingtips, and stabilizer.
Form these parts from wetted 1⁄32 strips.
Most hobby shops do not have the
light balsa and tissue needed to build this
model. An excellent mail-order source is
Peck-Polymers (see the company’s ad in
Model Aviation). To order the complete
catalog for $4, which is a good
investment, call (619) 448-1818. Mail
order is a great resource. Peck is the best
for Free Flight.
You should order 1⁄16 and 1⁄32 balsa
(get small sheets and a dozen 1⁄16 square
sticks), 1⁄32 plywood, a sheet of yellow or
tan Esaki tissue, a 4-inch black square-tip
plastic propeller, a pack of 1⁄32-inchdiameter
shafts, a pack of white nylon
Peanut bearings, a pack of 1-inch black
plastic wheels (unless you want to cut
your own from white carryout tray foam),
a pack of 1⁄8-inch FAI Tan II rubber, a
Peck 5:1 winder for rubber, and the XActo.
Good books to have are Don Ross’s
Rubber Power Flying Models and
Building the Peck ROG by Bill Warner.
Both have many photos and excellent
drawings by Jim Kaman. They will be
treasured in your modeling library. Both
are available from Peck-Polymers.
If you have no stick-and-tissue
experience, order some simple kits: an
AMA Cub (Delta Dart), a Peck ROG, and
perhaps a Sky Bunny. These have
complete, illustrated instructions that will
make you skillful in a hurry. The Hawk is
not a beginner’s model!
Building: I will not tell you how to glue
Part A to Part B; the aforementioned kits
and books will teach you that. The simple
Cooper-Travers Hawk is not an ARF
(Almost Ready-to Fly) with an instruction
book; it is a craftsman’s project requiring
some basic skills.
The sliced wing ribs may be new to
you. Make a rib-slicing pattern from 1⁄32
plywood using the extra plans copy (gluestick
the pattern to the plywood). Cut a
sheet of 1⁄16 balsa to the length of the
center rib, then tape it to the cutting board
at the bottom of the balsa. Slice away
with the X-Acto knife at the top and
discard the scrap, then move the pattern
down 1⁄16 inch. Carefully slice again; you
may need a couple of light strokes.
Cut a full set of ribs. Taper them from
the rear before you glue them in place to
the leading edge and trailing edge. Note
that there is only one center rib, which is
added as you put in the 1-inch dihedral.
Be sure that half of the wing is pinned
down flat as you raise the other tip.
Another unusual method is the wet
lamination of balsa for the round-corner
tips, aileron ends, and fin/rudder. This
requires making forms from artists’
matboard or 1⁄16 balsa; see the photo.
Using the extra “patterns” photocopy
of the plans, glue-stick the tips (one on
each wing and stabilizer) and fin/rudder
to the pattern material. Cut to the inside
line of the double lines of the curved part.
Allow some extra (straight) beyond the
end of the curve; this is for taping the
lamination to the form.
The lamination will be two strips of 1⁄32 x
1⁄16 that appear 1⁄16-inch wide on the plans to
match the 1⁄16 square sticks. Lightly sand the
edges of the patterns and wax them to
prevent glue from sticking the part to the
form.
Cut the strips to length a bit longer than
the form edge, and soak them in hot water
in a saucer. Two at a time, blot excess water
with a paper napkin. Apply a bead of
Titebond or Elmer’s carpenter’s glue to one
strip, then stack the other on top of it,
wiping away any glue that leaks out the
edge. Your lamination is ready to bend
around the form.
Cut two small pieces of 3M Scotch
Magic Tape to hold down the ends. Affix
one end of the strips to the form, pull firmly
and tight to form around the curve, then
affix the other end. Now you are ready for
the fun part.
Put a coffee mug upside down in the
microwave and set the wet part/form atop it.
Microwave for one minute on high, and
presto! You have a permanently curved part
that only needs cutting loose from the form
at the ends. Cut to the line you see at the
end of “straight” for exact length. Discard
the excess with tape. Repeat until you have
all parts; the stabilizer and wingtip/aileron
forms get used twice.
This is the easy way to make curves on a
Finished parts ready for assembly. Black propeller is smallest North Pacific/Peck size.
You can clearly see the undercambered rib strips. The wheels are made from 1⁄16 sheet
foam with silver paper hubs.
38 MODEL AVIATION
stick-and-tissue model—and it’s much
easier than cutting segments of curves from
1⁄16 balsa sheet and piecing them together.
This is how they did it in the 1930s, but
they did not have such water-based glues or
microwaves then. Technology can make
building faster and better.
Assembly and Painting: After parts are
covered with tissue (use the glue stick on
balsa, then pat the tissue down and trim),
mask off the ailerons, rudder, and elevator
with low-tack masking tape and paper. If
you do not want an accurate color, simply
use the colored tissue. Note that the flying
surfaces are covered on the top only and the
body/fin left side only.
Get a can of Krylon Short Cuts acrylic
aerosol in Espresso (color SCS-035). It will
give your tissue a coffeelike tone—similar
to aged shellac on 1924 aircraft fabric.
Carefully mist a light coat on the exposed
tissue and let it dry before unmasking. Paint
the nose with aluminum acrylic paint from
Wal-Mart.
Attach the rear hook and bearing to the
motorstick (see details on plans), then glue
to the right side of the body as shown on
the plans. Attach the stabilizer, then attach
the fin to the body. Tilt the right side of
the stabilizer up slightly, as seen from the
rear; this will induce a natural right-turn
circle.
Attach the wing to the top of the body;
you may want to pin it at the leading edge
and trailing edge while the Duco dries.
Check to make sure that it is level.
Attach the splayed 1⁄32 plywood landinggear
struts and add the wheels, which can
be glued on. Rotating wheels are not
required; this model is hand launched only.
Add the 1⁄32 plywood rear skid.
Make a rubber motor in approximately a
12-inch loop, tying the ends in a square
knot. Lubricate the motor with Johnson’s
Baby Shampoo and wipe off the excess.
Hang the motor from the shaft and the
rear hook, then wind in a few hand turns,
rotating the propeller clockwise while
holding the nose. Let the propeller breeze
blow in your face—it’s cool!
Check the balance (see plans) with the
motor installed. If necessary, add clay to
the nose in the sheeted section. Correct
balance is essential for Free Flight—or for
any aircraft, piloted or not.
Go to a copy shop and ask for a
discarded box used to ship letter-size copy
paper. Do not use grocery-store boxes; the
lids implode. Put your model in your
storage/transport box, but don’t put any
heavy objects in there with it—a rolling
winder could damage the model.
Flying: It is pointless to test-glide such a
small model. If you fly outdoors (it is
okay to fly in a school gym if it is windy
outdoors), hand wind roughly 200 turns
into the motor and launch the model
straight and level into the wind (10 mph
or less). Do not throw the model!
Your Hawk should fly in a loose right
circle, climbing slightly. Adjust it by
bending the nose bearing to the right for
right thrust and bending the right aileron
down by cracking the tip ribs slightly and
gluing them. This will keep the wing up
(like an aileron) in a turn.
Progress to stretch-winding with the
Peck winder. You will need a flying
buddy to hold the model (upside-down)
by the nose bearing/propeller hub while
you attach the winder and stretch the
motor out approximately twice its length
to the rear.
Put in roughly 100 winder turns while
coming in, then remove the motor from
the winder and attach it to the rear hook.
Take the model from your buddy (give
him/her the winder), and gently launch it.
It should climb out in a loose right circle.
I hope you enjoyed the aviation history
and building this replica of an ill-fated
aircraft. Good luck with your Cooper-
Travers Hawk. Happy landings!
For an issue of the 7/01 Aeroplane
Monthly, send an airmail letter to the
Circulation Department, Aeroplane
Monthly, King’s Reach Tower, Stamford
St., London SE19LS, England.
The cover price is 3.20 pounds, but the
back-issue price plus postage would be in
euros. The easiest way to pay is by major
credit card so there is no trouble with
exchange rates. Include your name as it is
printed on the card, the card’s expiration
date, and the name of the card. That will
expedite your order.
You may order a copy by inquiring by
E-mail to [email protected] or
[email protected]. MA
Dave Linstrum
4016 Maguire Blvd. Apt. 3314
Orlando FL 32803
June 2003 39
Test pilot Lt. Col. Jim Travers flies Cooper-Travers Hawk on approach at Croydon (original London airport) on February 14,
1924, just seconds before fatal crash on first flight. Extremely deep undercambered Gottingen airfoil and 5° positive
incidence on tailplane were likely causes for crash. Ink sketch by author is from photo by Cecil Arthur Rae, who was later a
test pilot for British aircraft manufacturer Boulton Paul.