Cessna 152 landing Flap 30 or 20?
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Cessna 152 landing Flap 30 or 20?
Any body here land flap 20 as a matter of routine? we have a 1000m tarmac runway, always vacate at the other end, thinking about runway occupancy times etc, plus the fact that the cessna manual states to use the minimum flap needed for the crosswind, theres always a crosswind, flap thirty for a short field landing, any thoughts?
With 1000m of tarmac you can afford to land flapless.
With 30 flap you can practice really short field landings for when you need them.
Why not alternate? I can't, myself, see much reason to use 20 flap as it's neither fish nor fowl.
G
With 30 flap you can practice really short field landings for when you need them.
Why not alternate? I can't, myself, see much reason to use 20 flap as it's neither fish nor fowl.
G
Personally for the C 152/172 I taught 10 deg for crosswind, 20 deg for normal landings and 30 deg for short/soft field landings. This gave the students experience with all three settings. I also found that on the initial landing lessons students found it easier to manage the flare and transition to the landing attitude without ballooning when using 20 deg of flap vs 30.
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Students should be taught to appraise the conditions and runway and select the appropriate setting accordingly.
I have seen so many students “conditioned” to always using the same flap setting and then destabilising a perfect approach at 100’ by reconfiguring to that setting “because that’s what they were told.”
I have seen so many students “conditioned” to always using the same flap setting and then destabilising a perfect approach at 100’ by reconfiguring to that setting “because that’s what they were told.”
We have a sloping and relatively short runway, but I still use the same method as all the other clubs and schools I've been at for nearly 40 years. 20 deg for normal or crosswind, 30 deg for short/soft. I only advocate 10 deg for certain types of take off, not landing, because it's mostly extra lift without much extra drag. I see no reason to change but I'm still ready to learn if there's a compelling case for something different!
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many thanks for all the comments, i agree wholeheartedly, be flexible.
which leads me to ask about VS0, 35 kts on a 152, with full flap, so technically not protected to that speed with flap 20.
i like to hear the stall warner sqeak just before touchdown too, occasionally achieved!
which leads me to ask about VS0, 35 kts on a 152, with full flap, so technically not protected to that speed with flap 20.
i like to hear the stall warner sqeak just before touchdown too, occasionally achieved!
By definition, Vso is in the landing configuration (depending upon who you ask, Vs1 is either clean, or in whatever configuration you're flying at the time).
Regarding speeds - the C152 POH says 60-70kts flaps up, 55-65kts flaps down. Clearly, the difference there is weight - and I think that adjusting approach speed for weight is not taught enough, or well enough. Hopefully everybody here knows how to make that correction - but in my experience most PPLs don't.
G
Regarding speeds - the C152 POH says 60-70kts flaps up, 55-65kts flaps down. Clearly, the difference there is weight - and I think that adjusting approach speed for weight is not taught enough, or well enough. Hopefully everybody here knows how to make that correction - but in my experience most PPLs don't.
G
Any body here land flap 20 as a matter of routine?
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the C152 POH says 60-70kts flaps up, 55-65kts flaps down.
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Be careful using 1.3x the VS0 to calculate your own Vref. Calibrated airspeed should be used to calculate the proper approach speed at any landing weight and then converted to IAS for practical use. You should do this because, for some airplanes, the indicated airspeed near the stall has significant error.
Convert your IAS stall speed into CAS, multiply by 1.3 and convert that number from CAS into IAS.
Better still, use the speeds recommended in the POH.
SPEEDS FOR NORMAL OPERATION
Unless otherwise noted, the following speeds are based on maximum weight of 1670 pounds and may be used for any lesser weight.
Takeoff: Normal Climb Out 65-75 KIAS
Short Field Takeoff, Flaps 10°,
Speed at 50 Feet .... 54 KIAS
Climb, Flaps Up: Normal 70-80 KIAS
Best Rate of Climb, Sea Level 67 KIAS
Best Rate of Climb, 10,000 Feet 61 KIAS
Best Angle of Climb, Sea Level thru 10,000 Feet .... 55 KIAS
Landing Approach: Normal Approach, Flaps Up 60-70 KIAS
Normal Approach, Flaps 30° 55-65 KIAS
Short Field Approach, Flaps 30° 54 KIAS
Balked Landing: Maximum Power, Flaps 20° 55 KIAS
Maximum Recommended Turbulent Air Penetration Speed: 1670 Lbs 104 KIAS 1500 Lbs 98 KIAS 1350 Lbs 93 KIAS
Maximum Demonstrated Crosswind Velocity 12 KNOTS
Unless otherwise noted, the following speeds are based on maximum weight of 1670 pounds and may be used for any lesser weight.
Takeoff: Normal Climb Out 65-75 KIAS
Short Field Takeoff, Flaps 10°,
Speed at 50 Feet .... 54 KIAS
Climb, Flaps Up: Normal 70-80 KIAS
Best Rate of Climb, Sea Level 67 KIAS
Best Rate of Climb, 10,000 Feet 61 KIAS
Best Angle of Climb, Sea Level thru 10,000 Feet .... 55 KIAS
Landing Approach: Normal Approach, Flaps Up 60-70 KIAS
Normal Approach, Flaps 30° 55-65 KIAS
Short Field Approach, Flaps 30° 54 KIAS
Balked Landing: Maximum Power, Flaps 20° 55 KIAS
Maximum Recommended Turbulent Air Penetration Speed: 1670 Lbs 104 KIAS 1500 Lbs 98 KIAS 1350 Lbs 93 KIAS
Maximum Demonstrated Crosswind Velocity 12 KNOTS
G
50 years ago I was taught to use 20 flap and 60mph for a normal powered approach in the Cessna F150, although we also practised 40 flap 50 mph short landings (2000 rpm). The aircraft certainly would go around with 40 flap at 50 mph; at 200 ft we accelerated to 55 mph and reduced to 30 flap, then 60 mph before reducing to 20 flap, then 65 mph before reducing to 10 flap, then finally accelerating to 70 mph before continuing a clean climb...
BUT,
The aircraft were brand new, usually with around 20 hours on them since leaving Reims. The props were also brand new - and most of us weighed rather less back then!
BUT,
The aircraft were brand new, usually with around 20 hours on them since leaving Reims. The props were also brand new - and most of us weighed rather less back then!
When I did my PPL one hot summer day we were practicing forced approaches in a C 150. My instructor like go right down to around 100 ft AGL before calling for the overshoot. So there I am flaps 40 speed right on and in a good spot.
Go around he says, power up flaps up and nothing happens. The flaps had failed full down. My instructors took control and we were about 10 miles from the airport. The airplane would not climb and would just maintain height. We flew home at 100 ft with the instructor avoiding houses and power lines with very gentle turns.
After that hat the rule was no forced approaches below 500 ft AGL
Go around he says, power up flaps up and nothing happens. The flaps had failed full down. My instructors took control and we were about 10 miles from the airport. The airplane would not climb and would just maintain height. We flew home at 100 ft with the instructor avoiding houses and power lines with very gentle turns.
After that hat the rule was no forced approaches below 500 ft AGL
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My school uses 20 degrees up to first solo. I always make a big point of briefing the concept of 'lift flap' against 'drag flap' before starting landings and at some early stage introduce the flapless approach to demonstrate that there's nothing magical about any setting. Hopefully our students leave us understanding that flap is a tool to be deployed depending on the field and the day.
It’s not just about the approach. We should be landing with the minimum groundspeed - even if you have 1000s ft of runway. If a tyre goes or some other mishap, far better it happens a min speed in my view. Consequently, I teach to use the most flap the conditions will allow
rarelyathome
I agree with you, the third stage of flap is put there to assist the aircraft to land and it lands better with it. Once experienced, the pilot can make decisions to match the circumstances and by then will have the capacity to deal with any other eventualites that may occur.
I agree with you, the third stage of flap is put there to assist the aircraft to land and it lands better with it. Once experienced, the pilot can make decisions to match the circumstances and by then will have the capacity to deal with any other eventualites that may occur.