Cessna
Model 172 Skyhawk
Cessna designed the Model 170 and its
successor the Model 172 as "family" aircraft. Both planes were enormous commercial
successes, and have been built in larger numbers than any other aircraft to
date.
The Model 170 was designed in 1947. In this model, the landing gear was in the
convention "tail dragger" design, with an all-metal fuselage and a
cloth-covered aluminum wing. In the
mid-1950s, the Model 172 was introduced, which was essentially the same plane
as the Model 170, but with a squared-off tail rudder and tricycle
"Land-O-Matic" landing gear with a steerable front wheel for
taxiing. Although this fixed-gear
design adversely affected aerial performance, it was a huge commercial success.
The plane has room for four; one pilot,
one instructor, and two passengers.
Although typically a civilian aircraft, Cessna delivered a number of
Model 172s to U.S. forces between 1966 and 1970. These planes were used for pilot screening and elementary flight
training. The plane was also license
built by Reims Aviation in France beginning in 1963.
The Model 172 burns 6 gallons of aviation
fuel per hour at routine usage. A full
load of fuel costs $10.60 (or $315 in 2006 dollars).
Cessna
Model 172R Skyhawk (TL7)
Subassemblies:
Light Fighter chassis +3; Recon wings with STOL option +2; 3 fixed wheels +0.
Powertrain: 119-kW aerial HP gasoline engine with 119-kW
prop and 53-gallon standard fuel tank [Wings].
Occ.: 2 CCS and 2 CPS Body.
Cargo: 0
Armor F
RL B
T U
All: 2/3 2/3 2/3 2/3 2/3
Equipment:
Body:
Backup driver option, medium radio transmitter and receiver, navigation
instruments.
Statistics:
Size: 35' 7"x26' 11"x8' 9" Payload: 0.57 tons Lwt.:
1.15 tons
Volume: 144 Maint.:
131 hours Cost: $2,297
HT: 7.
HPs: 25 Body, 35 each Wing, 5
each Wheel.
aSpeed: 139
aAccel: 2.5 aDecel:
9 aMR: 2
aSR: 1
Stall
Speed: 49 mph.
gSpeed: 147
gAccel: 7 gDecel:
10 gMR: 1
gSR: 3
Ground
Pressure: Low. 1/3 Off-Road Speed.
Design
Notes:
Although the Model 172R crosses the line
into TL7, the above craft was designed at TL6.
It could still represent almost any of the early or current Cessna
Models. The current cost for a Cessna
172 is around $100,000.
The design exceeds actual take off weight
by 500 lbs. despite reducing the weight (and cost and HPs) of the chassis by
50%. Crew/passenger weight may be a bit
excessive--the pilot I flew with was running calculations to check takeoff
weight despite the four people weighing 170 lbs. or less.
The design purchases 60 gallons of gas
tanks. The actual value is listed. Calculated aSpeed and Stall Speed are 129
and 38 mph respectively; the actual values have been substituted.
Actual wing area is 174 sf and was used
for all performance calculations. Using
the calculated gSpeed at 1/3 Off-Road speed (49 mph), the plane can still meet
its stall speed of 49 mph (or exceed 38 mph, if your use the calculated values
for both instances), and could potentially get airborne in a bumpy field, at
the GM's discretion.
Variants:
Cessna liked to introduce new models
annually (like automobile manufactures) for marketing reasons.
The Model 172 was first designed in
1955. It was powered by a 108-kW
engine. 3,757 built.
The Model 172A replaced the 172 in
1960. It has a swept vertical tail
surface that improved looks but not performance. 994 built.
The Model 172B (1961) had shortened landing gear, a baggage
door, and a redesigned cowling. 989
built.
The Model 172C (1962) increased maximum
takeoff weight. 810 built.
The Model 172D (1963) redesigned the
fuselage to allow for the "Omnivision" rear cabin window. 1,011 built.
The Model 172E had electrically actuated
flaps. 1,209 built.
The Model 172F had a more modern
engine. 1,400 built.
The Model 172G was a 172F with only minor
changes. 1,474 built.
The Model 172H had a redesigned nose gear
and new engine cowling. 1,586 built.
The Model 172I introduced the new
Lycoming engine. 649 built.
The Model 172K (1971) had enlarged side
windows. 2,055 built.
The Model 172L (1972) has a larger fin
fillet, and other minor changes. 1,535
built.
The Model 172M (1973) introduced a
drooped leading wing edge to improve stall characteristics. 6,825 built.
The Model 172N (1977) installed a more
powerful (but problematic) 119-kW engine.
The Model R172K Hawk XP was a 172N with a
145-kW Continental engine.
The Model 172RG Cutlass (1981) featured a
new 134-kW engine, a three-bladed propeller, and retractable landing gear. 1,191 built.
The Model 172Q Cutlass (1982) was the
172RG with fixed landing gear. 391
built.
Production of the Model 172 ceased from
1986 to 1996 due to product liability laws, which held manufactures responsible
for virtually any accidents involving their aircraft.
The Model 172R Skyhawk (1997) is the only
current production model. It features a
119-kW engine, fixed-pitch propeller, and new avionics.
From the Aerodrome for GURPS
© 2008 by Jim Antonicic