Fly Baby Owner Survey Results
Updated 27 October 2001
This page summarizes the results of surveying Fly Baby owners regarding
their experiences. The intial version of this is based on 20 responses
that Pete Bowers received in 1989, and I have added several responses.
Unfortunately, Pete didn't collect the data based on building hours.
Instead, what is logged is the start date and the date of completion.
For the examples received so far, the average time of construction is:
Engines were installed on the following percentages:
65 HP: 50%
75 HP: 10.7%
85 HP: 17.9%
90 HP: 3.6%
100 HP: 10.7%
115 HP: 3.6%
125 HP: 3.6%
Most are Continentals; the 115 HP and one of the 65 HPs was a Lycoming.
The 125 HP engine is a race-tuned A-65 from a Cassut.
Here's a comment from the owner of one of the 100 HP (Cont. O-200) Fly
Babies: "Hard to hold takeoff direction down runway on full-power
takeoff. Higher powered engine and narrow landing gear probably contribute
to this. Also rudder very sensitive. We use partial power for
take off until airborne."
Propeller sizes are described by the combination of the prop diameter and
the pitch: 70 x 45, where it's 70 inches in diameter with a 45-inch
pitch. Prop designations usually incorporate this; McCauley props
have part numbers like ACM6948 (diameter 69, pitch 48) and Sensenich units
will be called things like 74AK-2-46 (74 inch diameter, 46 inch pitch).
Generally speaking, if you have a larger engine, you need a larger-diameter
and greater-pitch prop to take advantage of the extra power. If you're
underpropped, the engine reaches redline speed at lower throttle settings,
and if you're overpropped, the engine can't turn enough speed to produce
maximum power. From looking at the survey results, it looks to me
like some of these airplanes have the wrong props for their propeller size...you'll
see some larger engines turning smaller props than some of the A-65 examples.
What we're probably seeing here is folks basing their prop selection on
what they can find on the used market, rather than having a new one made.
Here are the prop size results from the survey. My suggestion
would be to pick a prop in the middle of the ranges shown. I identify
the "standard" application for some of the prop sizes, these are from the
Aircraft Spruce catalog.
71 x 46 Metal
71 x 47 Metal
70 x 44 Metal
68 x 50 Metal (McCauley clipped tip)
74 x 46 Metal (Could be Sensenich standard prop for a 65-HP J-3 Cub)
72 x 44 Wood (Could be Sensenich standard prop for a 65-HP Aeronca Champ)
76 x 44 Sensenich Wood
72 x 42 Sensenich Wood (Could be cruise prop for 65 HP Taylorcraft)
72 x 44 Metal (pitch seems too low)
72 x 51 Metal
71 x 48 Metal (Could be McCauley metal standard prop for an 85HP Cessna
74 x 48 Metal Sensenich
74 x 51 Metal Hendricks
71 x 50 (McCauley metal cruise prop for an 85HP Cessna 120)
72 x 42 Wood (Could be cruise prop for a 65 HP Taylorcraft)
In the survey, about 75 of the props have been metal. Metal props
are a lot easier to maintain, but a lot more expensive.
Best way to show the range of empty weights is with a graph:
It's interesting to note the ~150-pound difference in the reported weights
with the same engines...
Problems and Experiences
Some of the builders provided in-depth information on some subjects.
Comments in various categories are summarized
Problems in Construction
These comments are combined from the "Comments on Plans And Construction"
and "Problems during Construction" categories. Of the 28 entries
I have, half of them say things like "Excellent" and "No problems."
Several left the categories blank. The comments below are all the
negative ones in these categories.
"Jig of axle to put on inside plates (welded). This bird sits with
one wing 2" low."
"None except for lack of money at the time"
"None other than getting some materials"
"Alternative flying wire to wing attachment drawings page 4-7 detail 3
could be more specific for through bolt dimensions (those 3/16 or 1/4""
4 and 6"" long bolts are expensive.... The biplane N strut attach spar
blocks T-2 on page 10-18 detail A does not appear to match dimensions for
N strut fittings. For early homebuilder plans these are very complete
and comprehensive, and a very good value at $65. I believe that my
airplane was constructed from Bowers' EAA articles, as wing spar spacing
is slightly different from full scale rib plans. "
"Marital and Geographic"
Comments on Flight Characteristics
"Has no bad habits and it easy to fly. Flies like a J-3 Cub or an
Aeronca Champ. Must maintain at least 1500 RPM while landing, easing
off as you settle in".
"It aint' no F-4 but it is a stout, honest, machine"
"Light on controls - it is an aileron airplane- fast sink rate in no-power
glide - beautiful to fly - stable"
"A joy to fly. Controls are pleasantly light and authoritative, yet
not too fast or twitchy. Very forgiving airplane."
"Very good - avoid crosswind takeoffs on rough fields"
"Hard to hold takeoff direction down runway on full-power takeoff.
Higher powered engine and narrow landing gear probably contribute to this.
Also rudder very sensitive. We use partial power for take off until
airborne. Very nice flight characteristics. Stalls gently,
"Due to added power and drag reduction, this airplane can be cruised from
75 to an honest 120 MPH. The added elevator trim tap makes it possible
to stay trimmed at any speed. Top speed is 130 MPH."
"Great plane - Very docile- easy to take off and land. Approach speed
70 MPH, touch down 60 MPH, stalls 45 MPH, max crosswind 15 knots"
"Gentle, easy to handle, hard to spin. Has higher sink rate during
landing approach than most planes."
"Flew hands-off first flight. Stall about 45, cruise about 90."
"It's a great fun airplane"
"Very docile and stable"
"Aircraft flew extremely well from first flight with only minor adjustments
to horizontal stabilizer incidence angle. An excellent first-time
project - safe!"
"Flew great hands-off"
"Very docile both in the air and on the ground. She is easy to land,
but like all taildraggers, attention must be paid during takeoffs and landing
roll-out. My airplane is slow, approximately 78 MPH indicated. Perhaps
a different prop would bring the speed up to 100 MPH. Also, my Flybaby
requires considerable rudder input for coordinated flight...she is not
a feet-on-the-floor airplane."
"Good- Straightforward stalls - spins fast, but recovers quickly."
"The most fun that you can have with your clothes on, Fly Baby monoplane
flies like a biplane with one wing thoughtfully removed for visibility,
back to basics flying from another era. Is pitch sensitive-neutral
pitch stability, good roll with little adverse yaw, good rudder.
Lots of drag, do not fall behind the power curve! If the airplane
gets too slow it falls down. Airplane doesn't pitch nose down in
the stall... but if the stall is aggravated, airplane breaks sharply without
warning into spin (rigging problem??); very docile in the 3 point position-ground
handling and take-off, a new pilot should get a tailwheel check-out
in a low power biplane or similar high drag tail dragger for check-out"
"With 280 # pilot, Cruise = 100 mph, Climb from 2400' field elev = 1000
fpm, Ceiling = 14000' " [Aircraft has 115 HP - RJW]
"The ailerons are a little slow and the elevator is a little quick.
It's a blast to fly. Cruise is about 100 mph climb is unbelievable
with the new engine, the 6X6.00 tires are a little sensitive on landing
but you get used to them."
"I had taken the plane to the Deer Park airport just north of Spokane,
Wa. I assembled it, checked everything out and proceeded to try some fast
taxi testing. I didn't have much tail dragger time, about 7 hours in a
Cessna 140, so was a little apprehensive. I put power to it and I had intended
to raise the tail and keep it on the ground but before I knew it I was
climbing out and it flew great. I made two circuits in the pattern and
"Very honest, basic aircraft. No vices. Most fun flying I've
had in approximately 44 years of flying."
"Built open-cockpit turtledeck per plans. Also a sliding canopy frame
of aluminum, pop rivets to hold plexiglass with silicone sealant.
To keep it closed, I used a suitcase latch with a hasp which has a wood
pin to keep the latch from vibrating open. Worked fairly well"
"The tailwheel steering horn on rudder was built per plans but tended to
flex. used a bolt-on brace of 1/4"" OD tuube with 0.064 tabs to stiffen
it. The compression rype tailwheel steering springs are more positive.
Also made up and tried a full-swivel/lockable tailwheel sort of like DC-3
or SNJ. Beautiful tracking on takeoff but busy taxiing."
"The seat per plans is a pain in the lower back. The ultimate I came
up with was a bottom aluminum bucket for the seat pack chute (Security)
or a folded sleeping bag. For back rest I used an aluminum pack frame
(as in backpacking) with extra back bands."
"On the pre-cover inspection, Flight Standards suggested guide rollers
on the aileron long pushrod. With a couple of thousandths play in
each bellcrank, etc. you can end up with a sloppy aileron system in comparison
to a cable system.."
"Since I couldn't get help even from FSDO, on all surfaces I first varnished
(Polyurethane) and then dope-proofed with synthetic enamel. I haven't
flown the plane for 4.5 years, kept outside all the time. The fabric
at the rudder/fin/elevator/stab/aileron spars started come loose 2 years
ago. No problem at fabric to fabric seams. Maybe sewing the
covers on would be a better idea."
"I would use modern brakes. Otherwise, none other than careful look
at wieght and drag reduction."
"Increase diameter of tail wheel mounting bolt from 5/16 to 3/8"
"Slightly taller landing gear (I raised mine 3") for more angle of attack
on ground, aircraft sits very flat - landings tend to be made tailwheel
first due to flat attitude."
"A little more accuracy with material and hardware requirements."
"FlyBaby must be taken for what it is, a basic airplane, simple and inexpensive.
The technology and flying characteristics are '20s/'30s vintage a la Pietenpol
and Longster. Pitch stability could be a little bit better with a
bit more stick force. An easier to build and less expensive ( note
comments in Plans and Instructions) wing wire to wing attachment could
be standardized, though the standard set-up is perfectly acceptable.
Those mentioned attach bolts are hard to get in the correct length, and
the 3/16 size is easy to damage by over torquing the nuts creating a safety
hazard. The plans should not give advice on glue use, as different
adhesives require different clamping pressures, nailing may not be correct
clamping pressure. A bushing in the for/aft control stick pivot attachment
to the torque tube could have a bushing. "
"The saddle for the tailwheel spring is attached to the bottom of the fin
spar and eventually the end of the spar crushes because the total tailwheel
load is applied there. I redesigned the saddle to carry the load to the
4130 "V" bracket at the fuselage tail post "
"MORE leg room. Our cockpit is a little short."
Note that these are NOT approved changes. These are changes individual
builders made. Not all are necessary, or even good ideas.
These are provided for information purposes only.
"Pressure cowl, different windshield, 600x6 wheels, changed to 800 x4"
"Used Aeronca carb air box, nose bowl, cowl like 7AC. Rosenhan wheels,
seat design, radio mount between legs ahead of stick on floor"
"Fiberglass pressure cowling layup over whire and plaster mould - windshield
modified slightly - elliptical wing tip not used with plan form modifed
slightly for 2 ft less wing span"
"Enclosed engine cowling based on PA-12 nose bowl. Toe brakes.
Gussetted all ribs in empennage, wings rib-stitched."
"Pressure cowling, metal landing gear legs, wing tips squared off"
"Pressure Cowl with nose bowl made from Cessna 140 Part.... Landing
gear V filled and steel axle faired with foam and covered with Dynel fabric
and epoxy. Elevator trim tab added. Aft turtledeck not removable.
Starduster windshield. Engine mount modified for O-200 engine."
"Two-seat version of Fly Baby. Flew as single seat for 228 hours.
Fuselage stringers added to round out fuselage shape."
"Wing to fuselage aft end was tapered, filled with foam, fiberglass covered."
"Sliding canopy, raised turtle deck, pressure cowl, heater."
"Fuselage made 34" wide, Cessna 140 engine mount used, lowered thrust.
All else standard. Planned to make it 2 place side-by-side, did not!"
"Clipped wing (24' span width with square tips)"
"Enclosed cowling, PA-11-type Rattray nose cowl, ercoupe spinner.
600x6 wheels and brakes, cherokee wheel pants, baggage compartment covered
with plywood, fiberglass fuel tank."
"Winter canopy - fits in place of open cockpit. Cowled engine moved
forward 1", steel gear 3" higher, trim system, 600x6 tires and wheels,
pants, instrument panel, balsa gap-fillers in tail"
"Pressure cowling; 18 gallon fuel tank; streamlined Steel tube landing
gear (tubing removed from scrapped prewar Junkers floatplane); 6:00-6 tyres
with wheel spats (changing to 8:00-6) with Luscombe 8 wheels & cable
drum brakes; flat wrap windscreen with sliding canopy; wood skinned ""D""
cell wing leading edges, 1/4"" wing wire bolts sans 3/16""; ply skinned
fin leading edge."
"Completely rebuilt the plane (two year effort) Changed engine added stringers
to round out fuselage, 6 in wheels, brakes from a Piper Arrow (over kill),
Added wheel pants, added larger flying wires, Moved the rudder pedals forward
for more leg room, Replaced all the sheet metal, changed pitot tube to
a Piper blade type, Rebuilt the landing struts moving the axle forward
about 2 inches to match the plans. Changed the harness to military type
(managed to get a new set from an E-3 when some general didn't like them.)"
"I had talked with Pete Bowers when I ordered the plans to get his thoughts
on making a two seater out of it and decided to go this route from the
start. I built the fuselage wider to 40", made the turtle deck taller,
increased the height of the rudder by one foot. I also increased the horizontal
stabilizer span to 10 feet, I figured the increased height of the turtle
deck and the increase in width would require more tail surface area. I
made an enclosed canopy with gull wing doors, put in a 100 hp Continental
0 200 A and have a full electrical and vacuum system. I think as far as
the plans and instructions go, they were great but I did a lot of modifying
to get what I wanted. "
Comments? Contact Ron Wanttaja.