Questions:
Click the green check mark on the left to see the answer

2.  How much weight can a Cessna 150-152 carry ?

3.  What kind of gas mileage does a Cessna 150-152 get ?

4.  How far can a Cessna 150-152 fly on a tank of gas ?

5.  How high can a Cessna 150-152 fly ?

6.  How much runway does a Cessna 150-152 require ?

7.  What is the "Stall" speed of a Cessna 150-152 ?

Answers:
Performance figures are averages of all models equipped with standard horsepower engines. Club Members can obtain performance specifications for individual models in the member's area.

Q:

 1. How fast do Cessna 150-152's fly?

A:

According to Cessna's specifications the cruising airspeed for a Cessna 150-152 is 105 KTS (nautical miles per hour), which equals 120 MPH (miles per hour). Like other airplanes, this speed is optimistic. When manufacturers test airplanes for specifications they set them up for the best possible performance, but production airplanes rarely meet the "book" numbers. Most Cessna 150-152 pilots agree that the airplane's average airspeed is closer to 95 KTS (about 110 MPH).

Keep in mind that airspeed is a completely different thing than groundspeed. Airspeed is really only useful for comparing the performance of different airplanes because it describes how fast an airplane moves through the air. Because the air is rarely still, the distance an airplane covers in an hour depends on which way the wind is going. Compared to cars on the ground, a Cessna 150 that is flying at 110 MPH may actually be going as fast as 150 MPH if a strong wind is going the same direction as the airplane ( tailwind ). On the other hand, if the Cessna is flying directly into a strong wind ( headwind ) it would only be traveling about 70 MPH compared to cars.

On a round trip, the wind speeds cancel each other out like riding a bicycle up a hill and then back down on the return home.  In practice, the winds typically vary from about 5 to 20 MPH, so the typical groundspeed of a Cessna 150-152 is between 90 MPH and 130 MPH. This is on the slow side for airplanes, but pretty impressive compared to automobile speeds.
[ top ]

Q:

2. How much weight can a Cessna 150-152 carry?

A:

The Short Answer:  Between 400 and 500 pounds.

The Longer Answer: The FAA specifies a legal maximum weight limit for all airplanes, known as "gross weight". For most Cessna 150's the gross weight is 1,600 pounds. (1,670 for Cessna 152's) For 150's prior to 1964, the gross weight was 1,500 pounds. Though the maximum weight is the same for each model, each individual airplane has a different minimum weight, depending on everything from what kind of radios are installed, to how the airplane is painted and what kind of upholstery it has. This minimum weight is known as the "empty weight" and doesn't include the weight of fuel.  Each airplane is weighed when it leaves the factory and it's empty weight is recorded. After that, each time something is added or removed from the airplane, regulations require that the empty weight be revised to show the new empty weight of the airplane.

The typical empty weight of a Cessna 150-152 is about 1,100 pounds. (depending somewhat on model, earlier airplanes are usually lighter, later models usually heavier, which pretty much negates any perceived advantage of higher gross weight in the later models.)

Figuring out how much an individual airplane can carry is a simple math problem: Take the gross weight, subtract the empty weight, and you have a good starting number, called "useful load". For example, if our gross weight is   1,600 lbs and our empty weight is 1,100 lbs, we have a neat 500 lbs of useful load. We'll need fuel of course, and let's assume for this example that we want to fill up the tanks. We will have to subtract the weight of the fuel in order to find out how much weight is available for people and baggage. The standard tanks on a Cessna 150 hold 26 gallons. Fuel weighs 6 lbs per gallon, times 26 gallons equals a total of 156 lbs. Subtract that from the useful load, and now we have 344 lbs available as "payload". The FAA considers that the average person weighs 170lbs, so that leaves room for exactly two average persons.

Of course in the modern world, many of us weigh more than 170lbs. For a solo pilot, this won't be a problem unless he or she weighs more than 344 lbs. If that's the case, he or she likely won't be able to fit in the airplane in the first place, so we can stop worrying about that.  The baggage area on most 150-152's can hold up to 120 lbs, which turns out to be really a lot of stuff. The baggage area is quite large on these airplanes ( big enough to hold an extra seat with a child weighing up to 110 lbs! ) For regular baggage ( clothes, snacks, etc) there is both enough room and weight capacity for a solo pilot unless you happen to be traveling with your bowling ball collection.

The problem arises when we add a passenger. Let's assume that we have a typical couple, a female pilot weighing 130 lbs, and her male passenger weighing 190 lbs. Since their combined weight is 320 lbs, each would be able to bring along a suitcase weighing up to 11 lbs. If the people weigh more than that, or they need to carry more baggage,  the only option is to carry less fuel. With full fuel the airplane can safely fly for about 3 hours*. Each gallon removed reduces the available flight time by about 10 minutes. If the anticipated flight is only 2 hours long instead of three, the pilot could elect to put 20 gallons of fuel in the tanks instead of 26. In that case there would be room for 36 additional pounds of people or baggage.

*fuel endurance is highly dependant on both pilot technique and environmental conditions. The figures quoted are averages, and not to be used for flight planning. Your mileage will vary.
[ top ]

Q:

3. What kind of gas mileage does a Cessna 150-152 get ?

A:

The Short Answer:  Between 15 and 22 miles per gallon.

The Longer Answer: A great way to calculate gas mileage for an airplane is to compare it's efficiency to a car. For starters,  an airplane flies in a straight line ( as the crow flies, more or less ), while a car must follow the roads, which commonly deviate around both natural and man made obstacles. A 300 mile road trip in a car would typically be reduced by about 15-20% in an airplane.

A comparison of a 300 mile trip in a Honda Sedan vs. a Cessna 150: Using conservative averages, we will use the government "combined fuel average" for the Honda Accord of 28 miles per gallon, and assume that the Honda will average 60 miles per hour.

For the Cessna 150, we will assume a reduced distance of 15%, a reasonable average speed of 110 miles per hour, and an average hourly fuel burn of 6 gallons. 110 miles divided by 6 gallons = 18 miles per gallon.

Vehicle	Distance	Time Enroute	Gallons per hour	Total Fuel Used
Honda Accord	300	5 hours	2.1	10.2 gallons
Cessna 150	255 (-15%)	2 hrs 20 min	6	14 gallons

In this case, though the Honda is more fuel efficient, the Cessna is clearly more distance and time efficient.  Notice that the Cessna used 38% more fuel, but the trip took 118% longer in the Honda. We can even make a direct comparison of the fuel costs of the trip because like the Honda, the Cessna can be operated on regular unleaded car gas. If we assume a cost of $4.00 per gallon, it would cost a total of $15.60 extra to make the trip in the Cessna. Not a bad premium for turning  a 5 hour road trip into a  2 hour and 20 minute flight.
( And the view's better ! )
[ top ]

Q:

4. How far can a Cessna 150-152 fly on a tank of gas?

A:

The Short Answer: This is a fairly simple math problem. For starters, we know that the Cessna will use between 5 and 9 gallons of fuel an hour, (depending on the individual plane, and how much throttle is applied by the pilot.) To keep this simple, let's average the high and low fuel numbers, which gives us an hourly average of 7 gallons. We also know that the average airspeed is about 110 MPH. The normal tanks on a Cessna 150 contain 22. 5 gallons of useable fuel. We don't want to run out of fuel, so let's make sure we land with a half hour of gas left over. Using the average above, we will need 3.5 gallons in the tank when we land. That leaves us with 19 gallons of fuel to use for the flight. 19 gallons divided by 7 gives us 2.71 hours*  X  110 miles per hour = 298 miles of range with a 30 minute reserve.
*( 2 hours and 48 minutes )

The Longer Answer: If we want to be more precise (and safe piloting technique requires that we do) we will need to pay attention to at least one more factor. For starters, we will need to know what the winds are, because that will determine how much actual ground we will cover in an hour. Since this is a hypothetical example, we don't have an actual destination, and therefore we can't determine the winds, so let's create a worst / best range instead.

Using the groundspeed averages from question #1 above, we will assume that the low end of the scale is 90 mph and the high end of the scale is 130 mph. Doing the same math as in the short answer, we can determine that the worst groundspeed and worst fuel consumption will give us a low distance range of 189 miles. The best groundspeed and best fuel consumption rate will give us a maximum distance of 494 miles. That's quite a wide range, and it helps explain why some pilots run out of fuel. If a pilot assumes that full tanks are plenty for a 250 mile trip but doesn't know there is a 20 mph headwind, that pilot stands a good chance of running out of fuel when they are still 50-60 miles and 30-50 minutes short of the intended airport.
[ top ]

Q:

5. How high can a Cessna 150-152 fly?

A:

The climb performance of individual model years of Cessna 150-152's are very similar, but Cessna seems to have changed their measuring methods from time to time, so the book maximum altitude figures ( service ceiling ) vary from a low of 12, 650 feet to a high of 15,300 feet.

In actual practice, the climb performance of these airplanes is sluggish above 9,500 feet. At altitudes above 9,500 typical climb rates hover around 100 feet per minute, so a climb from 9,500 to 12,500 feet could easily take 20 minutes to half an hour. Above that, both the crew and the engine are starving for oxygen. As a practical matter, Cessna 150-152 pilots rarely fly above 9,500 feet, it just takes too much fuel and patience to get there. The vast majority of Cessna 150-152 flying takes place between 2,500 and 6,500 feet.
[ top ]

Q:

6. How much runway does a Cessna 150-152 require?

A:

When it comes to runways,  Cessna 150-152's are surprisingly good performers for airplanes with relatively low horsepower. Like other specifications, the Cessna "book" numbers are a bit optimistic, Cessna claims the airplanes can take off in less than 750 feet, and land in less than 500.

Again wind pays a significant role. An airplane taking off and landing into a strong headwind will use only a small portion of the distance required without a headwind. At the Cessna 150-152 club national convention takeoff contest, one airplane used just 408 feet of runway for takeoff (into a headwind). If we remove wind from the equation, the realistic runway length requirement for a Cessna 150-152's takeoff is about 1,500 feet, about 750 feet is the realistic minimum runway length for landing. With a 10-15 knot headwind, these distances can easily be cut in half.
[ top ]

Q:

7. What is the "stall" speed of a Cessna 150-152 ?

A:

The Short Answer: 48-55 MPH (42-48 knots) with and without flaps.

The Longer Answer:  Most pilots know that an airplane does not stall at any particular airspeed, but rather at a given "angle of attack", this means that an airplane can stall at any airspeed and at any attitude. (this is demonstrated very effectively by modern aerobatic pilots who stall and spin their airplanes at high speeds as part of their aerobatic routines.) Why then are student pilots taught that the airplane will stall if it slows down too much?

Here's why: In a relatively low performance airplane like a Cessna 150-152, the engine does not generate enough thrust to keep the airplane flying at a combined low speed / high angle of attack. When the airplane is flown at slow speeds, the pilot must raise the nose of the airplane to keep it flying. As the nose rises, the wing gets closer and closer to a critical angle of attack, (sometimes called the "stall angle of attack"). Pilots are taught to keep the airplane flying above a certain threshold speed where this is likely to happen.

Every fixed wing airplane has a performance "envelope" that varies with aircraft weight, attitude, and environmental factors.   In a Cessna 150-152 the low end of this envelope is about 40 miles per hour, (about 35 knots). At this speed and below, the wing is producing so little lift that altitude cannot be maintained without exceeding the critical angle of attack, even in level flight. Attempting to climb over obstacles (like trees) or steer around them makes a stall likely. For the Cessna 150-152 the official "stall" speed (with flaps) is 48 miles per hour (42 knots). Pilots are taught to keep a margin of speed above what is likely to result in a critical angle of attack. This is why the recommended landing approach speed with flaps for the Cessna 150-152 is 60-70 MPH (52-60 knots).
[ top ]