Preparing for Flight: Pushing Back an Airplane
Aircraft · 7 min read
While pushing back airplane sounds quite straightforward, there are a number of steps involved in the procedure.
With an intriguing blend of qualities, the Cessna 120 and its sibling, the 140, are sturdy airplanes that have an eye appeal and are reasonably priced to buy and economical to own. Still famous for the qualities and features that made them popular in the late 1940s, such as a rounded rudder, conventional landing gear, and favorable overall proportions, Cessna 120/140 has the classic lightplane look and serves as a permanent solution to pilots need.
They are fixed pitch, single-engine, two-seat tailwheel airplanes belonging to the light utility airplane category.
Following the end of World War II, Cessna 120 and 140 were some of the most successful postwar light aircraft in the history and development of the Cessna Airplane Company, with almost 8,000 built between 1946 and 1951. They not only jump-started Cessna’s transition to a business but also provided a tremendous economic boost for postwar Cessna’s single-engine line.
After the War, aircraft manufacturers naturally assumed a boost in aircraft manufacture and production due to tens of thousands of Americans learning how to fly and gaining exposure to air transport. The first of the post-war Cessnas to be built in volume was the diminutive Cessna 140, followed by its budget version, the Cessna 120.
Cessna 120 has a very brief history as it was produced only for four years, from June 1946 to May 1949, with a price tag of $2695, owing to the firm training market potential. Cessna 140 was being sold at $2,995, and it differed from the 120 as it was equipped with an electrical system.
At the same time, the 120 was made very simple, initially lacking flaps, rear side windows, and standard equipment such as the electrical systems. Cessna built side-by-side seating, fabric-covered wings, and yokes instead of sticks, and the company also introduced two wing struts on both the 120/140 series. Since it started production in 1927, Cessna had never put struts on any of its airplanes, and doing so changed the public’s perception of the product line.
Over the years, most of the 120 fleets have been modified with electrical systems and other upgrades, and the absence of wing flaps is the primary difference between the 120 and 140.
Due to very little difference in aircraft performance with the split type flaps down on the 140 that were not much more than small speed brakes, 120’s lack of flaps is not a significant disadvantage as these airplanes fly very slow. The 140 was also equipped with an electrical system, generator, pull cable-actuated starter, quarter windows behind each door, and tube-and-fabric wings.
Introduced in 1949, the most desirable variant of the family is the 140A, with new all-metal tapered wings that were first developed in 1948, a single strut, more effective flaps, aft cabin windows, and a redesigned instrument panel. 525 140A were sold with three years of production. Although there are no design flaws in the 140, Cessna upgraded to the metal wings, which removed some of the aileron response.
Excluding the 140A with its standard metal wings and other older airplanes originally delivered with fabric wings that have had their fabric wings converted to metal, most Cessna 120 140 are still equipped with fabric wings. Some aircraft owners have reported costs of around $8,000 to $10,000 to replace the wing fabric, along with some minor internal repairs.
After the production of the 140A was shut in 1951, Cessna hung a nosegear on the basic 120/140 airframe and created the Cessna 150, which was the most successful training aircraft and one that owes its existence to the 120/140 line. Many a pilot owes their basic skills to this well-suited training aircraft.
The skins of the Cessna 120 and 140 are riveted over ribs in a conventional monocoque construction that is durable and was easy to fix even by the aircraft mechanics trained at the time of WWII by the military. The engines are four-cylinder, horizontally opposed, air-cooled, carbureted 85-HP Continental C-85-12 on both aircraft, and these are the least expensive ones.
The 140A offered the more powerful 90-HP C-90-12F engine in place of the 85-HP engine common throughout the 120/140 series and is liked due to its blend of low weight and higher power. A popular upgrade is the 100 hp Continental O-200. Still, since the rated horsepower is only attainable at higher rpm, many owners prefer instead to upgrade their C85s with an O-200 crankshaft as an STC that helps to provide additional power at a lower, more usable rpm range than the O-200.
Compared to other basic airplanes from the same era, Cessna 120/140’s instrument panel equipment has been upgraded by many owners with GPS and other instruments and basic IFR gauges and avionics. This venturi-equipped airplane can be flown in IFR as long as it is safe from freezing up.
With limited shoulder and legroom, the seats are 1940s-style bench designs, and taller pilots find their knees colliding with the yokes. As the seats are fixed in place, and the rudder pedals do not adjust fore and aft, short heightened pilots may need a pillow to reach the rudder pedals. Some owners have their airplanes modified with the seats of Cessna 150.
Cockpit visibility is marginal, and with the rear windows of the 140, as compared to 120 without a rear-window modification, it is better for the pilot. Unlike the post-war tailwheel airplanes that are tricycle gear airplanes, including even the Piper Tomahawk, the short cowling and flatter deck angle of the 120/140 is a significant advantage that aids the pilot in the ability to see properly over the aircraft’s nose. Toe brakes aid significantly in ground handling, and these are a vast improvement over the heel brakes found in the typical aircraft of this vintage.
Cabin noise is a major concern because of the small cabin size and close engine, with the exhaust dumped overboard very near the occupants’ feet. Cabin heating and ventilation are adequate. However, not up to modern standards. The front cabin windows are openable for ventilation during taxi, and many airplanes have been fitted with vents in the wing and/or blast vents in the side windows to improve airflow in hot weather.
Cessna 120 stalls at a speed of 32 Knots while 140/140A both have a stall speed of 43 Knots. The best rate of climb is 640 fpm in all three models, and so is the service ceiling of 15,500 ft. Wing loading for all three variants is 8.1 lbs./sq. ft.
Compared to other tailwheel airplanes, Cessna 120/140s relatively benign handling and better performance make it a better choice for aircraft owners. Cruise speeds of 100 to 110 mph are reached in the air from the 85- or 90-HP engines Cessna installed, with 4.5 to 5 gallons per hour fuel burn. This mainly depends on the engines as a slightly faster Cessna 150 burns six GPH, and a more modern engine like an O-200 or O-235 results in a higher cruise speed.
They have a minimum useful load, about 600 to 650 pounds. The maximum gross weight for the 120 and 140 is 1,450 pounds and 1,500 pounds for the 140A, while all have a standard fuel capacity of 25 gallons.
Heavier and more powerful upgraded engines such as the O-290 bring the airplane’s empty weight up to 1,050 pounds, leaving around only 250 pounds for people and bags. Most pilots prefer the fabric wing because of similar weight concerns as it tends to weigh 30 to 50 pounds less than those that have been metalized. Cessna 140 has 5 quarts, while 120 and 140A’s oil capacity is 4.5 quarts.
The fabric wing also provides nice flying characteristics, and the effective rudder contributes to making takeoffs straightforward. It also has good crosswind characteristics on both grass and paved runways, and this is due to the large elevator and tail surfaces. Unlike the typical Cessna, it has a lighter pitch and does not have massive adverse aileron yaw. It owes its stability to the wing dihedral and has an exceptionally docile and predictable stall.
Although landing a Cessna 120/140 is not very difficult, and it has better visibility over the nose, wheel landings do require more attention, particularly on lumpy grass strips. Being relatively light, it does tend to do ballooning on the landing, which can happen due to a misjudged flare or an effort to force the airplane onto the runway with too high a speed.
The aircraft had a nose-over tendency, and to overcome this, many 120s and 140s have been modified with gear extenders which are blocks on the main gear legs that move the wheels a few inches forward. Later 140s and all 140As addressed the concern with redesigned gear legs that were slightly swept forward to help counteract any nose-over tendencies.
With a gross weight of 1450 lbs, both the Cessna 120 and 140 are too heavy to be considered a light-sport aircraft or LSA as the max gross weight for an LSA is 1320 lbs.
As of early 2020, there were 14 140s and two 120s listed for sale in various places, with a median price of $25,000. Comparing to airplanes sold in the 1940s, the cost of Cessna 120 was $2695.
These prices are affected by typical factors, including the airframe time, engine time since major overhaul, and the aircraft’s general condition. However, two particular items affect the 120 and 140 more than many other aircraft types: the fabric condition and engine type.
Cessna 140 and 120 were an immediate success, and almost 8,000 aircraft were built between 1946 and 1951, along with 525 140As. More than 2500 Cessna 120 140 currently remain on the FAA register with 674 120s, 1,653 140s, and 235 140As.
Lower costs of operation are the main reason behind the large sales of vintage airplanes, especially in the case of Cessna 120/140. Apart from engine overhaul, the major cost for a 120 is re-covering the wing fabric, and depending on the conditions, the recovery intervals range between seven and 20 years.
In the case of metal wings, they result in reduced maintenance costs but come with the weight penalty of about 30 to 40 pounds. Most owners prefer the weight penalty over the maintenance costs, and these airplanes aren’t bought for the massive load-hauling capability.
The weak spots for the 120/140 include corrosion in the carry-through spar as the cabin skylight leaks water into this structure, creating a lot of moisture. Cracks in the tail structure and rear fuselage are another problem, with the airplane’s tail being the weakest part of the design, which is the most vulnerable around the tailwheel attach point. This, however, is repairable.
The landing-gear boxes, which are the support structure for attaching the landing gear to the fuselage, get damaged over the years due to hard landings and can be then inspected accordingly.
Another common weak point is the frequently broken tail springs that cause complete loss of control on landing and could lead to major damage to the airplane, particularly the elevators. It is essential to inspect these springs at regular intervals.
Two companies, Univair in Aurora, Colorado, and Wag-Aero, of Lyons, Wisconsin, supply high-quality parts for repair and refurbishment of the 120/140 such as gearbox assemblies, new cowling assemblies, and other often-needed and hard-to-manufacture parts.
A wonderful blend of character and qualities makes the 120 and 140 stand out and ensures that every flight is interesting, rewarding, and memorable. Provided an owner can live with a limited payload and leisurely performance, these are airplanes that keep their owners interested and enthusiastic for a long time.