flying the Cessna C150


 

Late Model C-150

A 1975 C-150M flies essentially the same as do 152s. The horsepower difference between the Lycoming and Continental is not really noticeable. The engine TBO is significant. Late model 150s are about the same as the 152 except for the different engine, 40 degrees of flap (150) vs 30 degrees maximum deflection on the 152, a different flap switch and indicator, 14 volt vs 28 volt electrical system, and 22.5 vs 24.5 gallons of useable gas (same 26 gallon total). The 150M has the same rudder as the 152.

Nose-wheel

Conventional gear aircraft fly much the same as tricycle aircraft. It is the landings that require special instruction and endorsement. This is because of the predilection to ground loop. Tricycle aircraft will align with the direction of travel if weight is kept off the nose wheel. There is a significant design difference of the nose wheel between Cessna and Piper. On the ground, Piper steers heavily and positively; Cessnas have springs that will gradually pull the wheel into the turn. The left and right turning springs of the Cessna are usually of different tension. This means that more differential toe braking will be required in one direction than in the other.

In the air, a Cessna nose wheel will hang down about a foot. This frees it from the socket that has the turning springs. The Cessna nose wheel will face forward and not move with the rudder. In a cross-wind landing the Cessna nose wheel is aligned with the direction of aircraft motion. The nose remains so aligned even in a cross-control landing. Again, the nose wheel should not be allowed to touch down during the initial landing but only because it is not designed to with stand such shock. The turning springs of the Cessna will not function until the nose wheel strut is sufficiently compressed. If you make a landing that seems to prevent steering except through differential braking, apply the brakes to compress the nose strut. The nose wheel geometry of Piper aircraft is completely different. (See nose-wheel landings and Piper)

The Cessna's nose steering is coupled to springs, and it's only movable 10 degrees) either side, unless differential braking is used. Braking will then caster the wheel to 30 degrees.

C-150 Flaps

The C-150 has slotted Fowler "barn doors" that, along with inadequate instruction, caused the C-152 to be "improved (?)" with only 30 degrees of flap extension. Flap speeds should never be exceeded since they put structural strain on the wings' rear spar. In most Cessna a 10-knot buffer below the high end of the white arc has much to recommend it. Any parasitic drag caused by flaps increases as the square of the speed. In some cases 10 degrees of flap may be used for takeoff but they should be removed at a safe altitude to improve climb performance. The reduction in flaps extension also allowed a higher gross weight to be allowed.

C-150 flaps have evolved from the Piper like Johnson bar through various flap switches and indent levers. Be careful, some switches work 'backwards'. The later models of the C-150 have electric flaps with indicators marked in 10 degrees to 40 degrees. There is a flap-shaped switch, which applies power to an electric motor and a worm gear to the flap-actuating rod. Extension takes about nine seconds and airstream assisted retraction takes about five seconds. Any count system used to move flaps should be figured accordingly. The flap indicator works on a cable + pulley system which has variations in accuracy. Different year models of the C-150 and all other models have different modes of switch operation. Be sure to check method of operation before flight and during checkouts.

A C-150 after landing with full flaps will be trimmed for level flight and will require 1 trim down movement of the wheel for climb. The C-172 will be trimmed for climb and will require 1 trim+ for levelling off. Most Cessnas do not recommend flaps for short field takeoff where Vx is required to get over an obstacle. Getting off the ground early will not help you get UP. The C-150 can have an abrupt pitch up when full power is applied in a full flap configuration. This could result in a departure type stall. The nose must be prevented from rising above the horizon by locking the elbow before applying any power. See "Go Around.

Trim and the C-150

From cruise trim to best rate climb is one full trim down not be pinching but finger tip at very top to very bottom.. From cruise to 1500 rpm four finger tip trims down and then back to 2000 rpm gives no flap minimum controllable. The same operation with only three trims down gives no flap slow flight at 60 knots. The same operation again but leaving the power at 1500 gives a 60 kt descent. The transition from pattern slow flight to descent requires only a reduction of power, easy.

Every 10 degrees of flap has a one to one relationship to a full finger tip turn of trim from the above configuration. From the 60-kt 1500-RPM power glide an application of 10 degrees flap lowers the speed to 50 kts. A full finger tip trim movement up returns the speed to 60 kts. 20 degrees does the same, as will 30/40 degrees. When doing this process with a student for the first time be sure to bring to their attention that you are in a descent. Demonstrate how the addition of power can stop at any given point. Descents are an early source of student anxiety as are clouds, mountains, bumps, water, etc, etc.

A Cessna 150 has nearly the same trim setting for level cruise flight as is needed at 1500 RPM, full flaps and 60 kts descent. Thus, the full flap short approach requires no change in trim unless power is off. This setting is constant for nearly every loading. The instructor will help the student determine this initial setting. If the C-150 has been landed with full flaps it will be near the correct setting for level cruise but not for takeoff climb. From this starting point of the trim wheel the following apply:

1. For a takeoff climb at 65 kts, the C-150 trim wheel must be moved down one full finger tip turn from the full flap landing/level cruise position.
2. To level off from this climb it must be moved up one full finger tip turn.
3. Three full down finger tip turns from level will give descent at 60 kts at 1500RPM.
4. Trim down four finger tip turns for a no flap glide at 60 kts with power off.
5. Trim full down four finger tip turns for minimum controllable without flaps. About 2000 RPM no flaps.
6. For full flap slow flight or minimum controllable trim up one finger tip turn. Full power.
7. Most Cessnas have one full finger tip turn of the trim between level and climb settings.
8. In each case fine trim movement may be required.

Removal of the flaps during the go-around finds you trimmed for level cruise. One full finger tip trim down will give Vy climb at 65 knots. This same procedure can illustrate why, when making a short approach, reduction of power to 1500 and application of full flaps at the white arc will give you a hands-off approach speed of 60 knots.

Basic Manoeuvres

Climbs are initiated by simultaneous power. Pitch change and right rudder. Always anticipate that power and pitch will require right rudder so as to avoid those annoying 10-degree heading changes to the left. After initial pitch change and trim application, adjust pitch and trim for desired climb airspeed or rate. A constant airspeed over several thousand feet of climb will result in a gradually lower rate of climb. A constant rate climb in the same climb will result in a gradual decrease in airspeed.

Climbing Turns

… require that you anticipate…
1. More right rudder in right turns
2. Less right rudder in left turns.
3. Lower ias at same pitch variable with bank angle and power available.
4. Lower climb rate at same pitch variable with bank angle and power used.

Levelling off is best done by leading the selected altitude by 10% of the climb rate. Anticipate additional climb by trimming a full turn and hand-holding altitude during the acceleration phase before power reduction. Failure to reduce power on reaching level cruise speed is guaranteed to give altitude and airspeed oscillations that are going to be difficult to correct.

Descents

… during approach and cruise are nearly the same…
1. Lower power and decrease pitch. Watch heading.
2. Expect ias to increase. Reduce power.

Descending Turns

.. anticipate…
1. Higher bank angle will cause increase in descent rate at same airspeed.
2. Required left rudder to increase in left turns.
3. Less left rudder in turns to right.
4. Airspeed will increase at same pitch attitude.
5. Same airspeed and power increase will reduce descent rate.

C-150 as a Glider

… without hope of restarting engine: Immediately...
1. Airspeed to best glide-near best rate climb (Move trim wheel down as far as it will go.)
2. Below gross glides are 5 knots slower
3. Determine field and wind
4. Mixture out, fuel off
5. Magnetos off
6. Stop the prop

Pre-crash

1. Master off
2. Unlatch doors
3. Seats all the way back and locked
4. Tighten belts
5. Cover panel with padding

Consolation

1. Few controlled accidents result in fatalities (5.2%)
2. Panic will not solve anything
3. Upslope landing if possible

Precision Slow-flight C-150

Slow Flight--Any speed below normal cruise. Precision exists where you chose to place it. An airspeed 1.3 of power off, flaps up stall speed is one such speed used for landing approaches. Where the POH states a range of speeds, you should always practice at the lower number. Select a speed above and below the POH speeds for approach and practice manoeuvres at these speeds. Excess speed is very common on landings. Trim is the basic control of flying precision. Any change in power, speed, or configuration requires a trim adjustment. As a student you should strive for certain standards. 10-degrees of heading, 10-knots of airspeed, and 100-feet of altitude, as a pilot you should maintain 5, 5, and 50, and as a precision flyer you should reach 2, 2, and 20. The more you practice changing through the range of slow-flight speeds the better you will be able to anticipate the trim changes and power setting required. The sound and feel of the aircraft are a good indicators to notice and learn.

No Flap Slow-Flight

Clearing turns
Carburettor heat
Power to 1500
Use yoke to prevent any sink during deceleration
Set power to 2000
Trim four finger tip turns for minimum-controllable at 45 knots.
Trim three finger tip turns for slow flight at 55 knots.
Fine trim for airspeed
100 rpm gives one-knot airspeed change
Retrim for all power airspeed changes.


C-150 POH

1976 Cessna 150 Required Information
Conditions are standard, and weight at gross unless otherwise stated.
Maximum Range and endurance with 45 minute reserve
@ 7000' 340 NM for 3.3 hours Clean stall 48 KIAS
Sea level climb 670 fpm .......Flap stall 42 KIAS
Service ceiling 14,000'
Service ceiling is the maximum altitude at which an aircraft can continue to climb 100 fpm. The safety margin between the highest terrain and the service ceiling should be at least 5000'.

Absolute ceiling is the maximum altitude an aircraft can attain. At this point the cruise speed, best climb speed and stall speed all equalize. The aircraft becomes unstable and controls are unable to stabilize flight.

T.O. S.L. Ground Roll 735 Fuel 26 total 22.5 useful
......Over 50' 1385 Oil maximum 7 with filter
Landing Ground roll 445 6 maximum indicated
.....Over 50' 1075 4 minimum indicated
Maximum Gross Weight 1600 lbs
Wing Span 32? Prop length 69"
Wing Loading 10.0 lbs per squat. ft.
Power Loading 16.0 lbs per horsepower

Va (Manoeuvring speed) 97 KIAS @ 1600lb 88 KIAS @ 1300 lb.
Vfe 85 KIAS
Vno Structural cruise speed 107 KIAS
Vne 141 KIAS
Vs Minimum controllable
Vso Minimum controllable (with forward C. G.)
Vx best angle 56 all altitudes
Vy best rate S. L. 68 to 62 @ 10,000'

White arc 42 to 85
Green arc 47 to 107
Yellow arc 107 to 141

The bottom of the yellow arc represents the airspeed where the airframe can sustain a specific design gust without exceeding the limit load. This means the plane will not fold, spindle or mutilate if the gust is less than the maximum design gust of 50 feet per second (30 on older planes).

Red line @ 141 KIAS

Chandelles, lazy-eights, steep turns and spin entries 95 Kts. Spins are prohibited with flaps down.

The red panel light on the far right indicates high or low voltage. The split switches can act as a circuit breaker to protect the system Reset by operating switches off and back on. Do this only one time.

Maximum glide speed is 60 KIAS and windmilling prop
What if prop is stopped?

Power off landings: Without flaps @ 65 KIAS
With flaps @ 55 KIAS
Ground fire procedures?
Electrical fire procedures?

Glide range (no wind) at 60 KIAS
@6000' 8 NM
@3000' 4.5 NM

Altitude required to execute power off 180 degree turn.
Altitude required to execute power off 240 degree turn.

Carburettor Ice as affected by application/removal of carb heat.

Short field approach speed with 40 degrees of flaps is 52 KIAS

Maximum crosswind component is 13 Knots.

Figure fuel remaining in C-150 for flight from CCR to RNO.

What is the maximum weight authorized for the luggage compartment.
At gross weight the allowed C.G. travel is only five inches.

Fuel Consumption

Fuel consumption will vary widely from those of the aircraft manual. Cessna 150's have been known to consume up to 9 gallons per hour. A PA-28 180 can be out of fuel in 3 1/2 hours, from full tanks, if the carburetor is out of adjustment. Failure to know the current, as loaded, fuel consumption is just as dangerous as not checking the tanks in the first place. The psychological readiness of a pilot is in a large part made up of his intellectual awareness of aircraft and his own capabilities. Be on the ground after three hours.
For a Cessna 150, with a 100HP Continental O-200.
Climb. 100/10 = 10 gallons per hour. Leaned 8.3
Cruise 75/10 = 7.5 gallons per hour. Leaned 6.3
Descent 50/10 = 5 gallons per hour. Leaned 4.0

Fuel Gauges

By FAR the fuel gauges are required to read accurately only when the tanks are completely full OR empty. When the gauge reads at the quarter full marker on both tanks the manufacturer says there are only three gallons of fuel left. At best this is about 20 minutes worth.

Building a Checklist

The AFM checklists are skimpy without radio procedures and settings. Just as we update the weight and balance forms so should the checklist be updated to account for changes of procedure and addition of switches
and instruments in the cockpit.

Single pilots are most prone not to use checklists in familiar airplanes. Pilots are likely to use the checklist when things are easy. A distraction is the most likely reason for a pilot to neglect using the checklist. When there is too much to do and too little time to do it. A checklist that is unavailable, too long, and inefficient is the one most likely never to be used.

The single pilot should develop a flow pattern which is more organized than is the 'reading the checklist' method. The flow is a planned series of actions that begins at one point and proceeds through a pre-selected number of items to the last point. The number of items should never exceed the fingers on both hands and ideally uses only one hand. The flow and numbering insures that everything is done in an efficient manner. The items and flow are aircraft specific.

Finger-flow Checklist

1. Every required item must be included along with a finger.
2. Flows are best during the 'busy' times.
3. Flows should be segmented for areas of flight.
4. Flows should be logical and items should be touched.
5. Flow should be verbalized (Say aloud what you are doing)
6. A flow checklist is not for the infrequent flyer.
7. A flow checklist is not a substitute for a written checklist.

The transition to a higher performance aircraft will bring into the situation the good, bad, and ugly habits that have been learned while in training. Essential to any transition is use of trim, throttle, and airspeed control.
The POH checklist is designed to remind the pilot of the minimums required for safe operation. It is a memory aid used to overcome short-term memory loss. The checklist places in order a number of actions or procedures that require action or verification. A checklist is not a "how-to" manual. A checklist is a roadmap of what is to be checked.

A checklist has items ranked in importance. Critical items affect safety, non-critical items affect efficiency and convenience. A checklist title for a given phase of flight would identify when the critical items are to be checked, list them in an orderly sequence, and provide for verification. This touch and verify method is recommended by the FAA for single pilot operations. The non-critical item list should be triggered by the completion of the last critical item.

Checklists should be done when they will least cause flying problems. A heads-up positioning of the list is best. The closer you are to making the landing approach the less likely will be the completion of a checklist. 

Checklist Errors

… are of at least five types.
1. The list is ignored
2. A critical item is omitted
3. Verification is falsely noted
4. Use of the list is delayed
5. The list is not completed

Once you have developed a complete checklist, you should begin to refine and systematize the material over and over. The list of items should be shortened, combined, and revised until it actually fits into your flying as something you usually do, in the order you do it, and when you do it.

The emergency checklist should be a memorized for immediate action. Do what you need to do and then use the list to verify that nothing has been omitted. An inaccessible emergency checklist is useless.

Sample recommendations:
1. Use laser or jet printer if possible
2. Extended text should be in lower case.
3. Limit to 2 types of font for emphasis
4. Use black on white except for emergency
5. Avoid multi-colours except for different aircraft types
6. Laminate (after fifth revision) with non-glare plastic
7. Print size should vary with age of pilot.

Short Field Landing Distances

C-150
Take Off 735' /50' 1385 Landing Distance 445 /50' 1075

C-172 Take Off 945 /50' 1685 Landing Distance 550 /50' 1295

C-182 Take Off 795 /50' 1625 Landing Distance 545 /50' 1285

An airplane should not be expected to get out of a space where it has landed.

Performance Synopsis

Cessna-back of front cover:
Weight, speed, range, climb.
Service Ceiling, take-off, landing, stall
Empty weight, useful
Fuel, oil, propeller, engine

OPERATION:
Checklists
Preflight to post-shutdown
Fuel system-cautions/operation
Electrical system-cautions/operation
Gear system-cautions/operation
Engine system-cautions/leaning/operation

PERFORMANCE:
Take-off/landings/flap settings/gear
Climb/cruise/cold/hot
C-150 Take Off 735' /50' 1385 Landing Distance 445 /50' 1075

EMERGENCY:
Engine/fire/electrical/gear

LIMITATIONS:
Gross/load factors/speeds/engine
Weight-balance chart/graph

OPERATIONAL DATA:
Airspeed corrections
Stall speeds
Takeoff/climb/landing charts
Cruise/glide

1. Don't try to climb to 9,500 in a C-150 unless you must. A C-150 flight to Las Vegas can be a 12 hour roundtrip regardless of wind direction.

2. Select an altitude appropriate to the distance. Avoid 3000'. Remember local flights tend to stay below 3000. No need to go high for short distances. Most pilots tend to fly at even 500s even below 3000. Choose a unique altitude so as to avoid traffic. Above 3000 AGL you must fly according to the hemispheric rule. Fly at 7,500 or 8,500 to minimize traffic conflicts but be aware when you cross, parallel or fly airways. Be sure to check with FSS prior to flight or with Flight Watch if your flight will cross military training routes.

3. Choose an altitude appropriate to the terrain and airports. This means that route selection may be predicated on several factors.

4. Select an altitude appropriate to the winds. Winds usually increase in velocity with altitude. Plan accordingly.

Select an altitude with reference to special airspace restrictions, local hazards and cloud layers. (It is more likely to be a rough flight below clouds.)


LANDING (C-150)

Prelanding check( Go-around procedure)
Abeam the numbers:
Cruise power/IAS
Carb Heat
Pwr 1500/1700
Hold heading/alt
Trim Down 3
Fly 60/70
10 degree flaps 1-2-3-4-
Yoke forward
Trim UP 1
Fly 60/70
Pwr 1500
Clear
Turn base
20 degrees 1-2-3-4
Yoke forward
Trim UP 1
Fly 60/70
Pwr 1500
Clear
Turn final
Full flaps 1-2-3-4-5-6-
Yoke more forward
Trim up l (172 no change)
Fly 60/60

C-150 Rudder Jamming

After becoming aware of the locked rudder accident, the manufacturer (Cessna) notified TSB investigators that it is developing a new design for the rudder horn stop bolt to preclude the possibility of over-travel of the rudder. Cessna has notified the Federal Aviation Administration (FAA) Aircraft Certification Office that it is developing a service bulletin to offer the new configuration for all models of 150s and 152s produced after 1966.

Rudder Jamming Problems

According to the FAA, a CFI and Student were killed when they were unable to recover from a training spin due to
rudder horn jamming. During a 50-hour check the day before the accident, the right pedal rudder bar return spring and its lever arm were found to be broken on the accident airplane.

These broken pieces of the rudder control system were removed without replacement. On completion of the 50-hour checks, the airplane was returned to service with no reference to the outstanding defect, recorded in the logbook. On the surface this accident would appear to be more a result of the missing parts than a design defect, but the FAA believes it is possible for similar jams to occur, even when the rudder control assembly is complete and intact. We have been unable to verify the specifics of this accident as the details do not appear in the NTSB record. According to the Cessna Pilots Association, the accident in question occurred in 1998, leaving us wondering why it has taken until 2000 to issue an alert.

C-150 Glide

Weight has no effect on best glide ratio. However, the speed to be used will vary by weight. The lighter the aircraft the slower the best glide speed. For every 10% of weight reduction, reduce the glide speed by 5%. Ground speed should be increased by at least 1/3 of any headwind to improve penetration distance. When distance is unimportant you should glide at a minimum sink speed. 50 mph will give a sink rate of only 600-fpm. You will get an additional twenty seconds in the air for every thousand feet of altitude.

From 12,000' a C-150's 70 mph indicated is only 84 true air speed. Power off sink rate is 870 fpm reducing to 725 at sea level. Another 20% of glide distance can be obtained by pulling into a near stall and stopping the propeller. To restart the propeller without using the battery will take a dive speed in excess of 120 mph.

Fuel Problems of Cessnas

Significant fuel imbalance has been explained away as due to overflow venting pipes being pressurized by air in flight. However, it has been found to be due to fuel tank sealant obstructing fuel tank vent lines as well.
See Cessna service bulletin SEB 99-18

C-150 Production

22,138 total U.S. production (734 Aerobats (6943 C-152s)
Produced from 1957 til the 1977 C-150M

Cessna vs Piper

--Seat belt systems are somewhat different.
--Flap relationship to trim is unique one from the other.
--Best to have your own POH for every aircraft you fly.
--Most of the checklist items will have a different sequence
--The first item of your emergency checklist will be different.
--Manufacturer's instructions related to carburettor heat differ.
--Night and cockpit lighting systems require distinctive explanations.
--The manoeuvring and taxiing blind spots are usually quite different.
--One door system is more likely to accidentally open as the other is.
--Cross wind and ground handling in strong winds distinctly different.
--One flap system is more controllable and consistent than the other is.
--Seat adjustment systems are just different enough to cause difficulties.
--Never plan to immediately fly hard IFR in a newly transitional aircraft.
--The way you hold your hands on the throttle should be quite different
--One fuel system is twice as likely to cause an engine failure as the other is.
--POH numbers and explanations vary year to year and even within the year.
--You should always make your own aircraft specific operational checklist.
--Confirm the 'neutral' position of the trim setting indicator with actual trim position.
--Learn all you can about the failure modes of all unfamiliar instruments in either type.
--Gear retraction and extension of one is less likely to give problems than the other is.
--The way you use the rudder pedals and brakes have a VERY dangerous difference.
--The preflights are distinctly different with differing critical points where mistakes occur.
--Get some pre-flight cockpit time for reading the POH and referencing the cockpit to it.
--Run the trim wheel all the way up and down, manually and electrically to become familiar.
--Within the same models of each manufacturer there are wide critical airspeed differences.
--Both manufacturers have made wing, elevator and instrument changes affecting critical speeds.
--Distinct differences in handling when at gross and near either end of the centre of gravity range.
--With two exceptions, one type is more likely to have a stall/mush accident in all its models than the other is.

Aircraft Proficiency Checkout

Preflight
Removal and storage of cover
Checking time log/pitot cover and control lock storage
Cargo doors not to be slammed.
Refuelling procedures
Location of POH/weight/ balance and aircraft papers.
Cockpit lighting
Starting procedures
Priming without throttle
Propwash effects behind
Detecting carburettor ice
Taxi procedures
Mixture leaning
Power vs brakes
Controls set for wind direction
Run-up
Facing wind or local requirements
Use of hand brake/foot brakes
Magneto check drop comparison
Clearing fouled plugs
Pre takeoff
Clearing the bases and final
Confirming power available
First power reduction at 1000'
Levelling off
Allow acceleration before power reduction|
Setting 75%, rpm and leaning
Trim and use of auto pilot (Operation and failure modes)
Heading and altitude control
Coordination of flight
Radio Procedures
Initial call to ATC and follow-up
Non-tower airport operations (Pattern operations)
Light systems
Manoeuvre
Steep turns
Slow flight
Stall recognition/recovery
Emergency procedures
Simulated engine failure
3 take offs and landings to include
No flap
Short approach
Short and Soft
Full flap go-around