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When do you NOT use flaps landing?

The last time I was hijacked... it was because I dind't do the dishes.
And ground control didn't even seem interested. And I PAY my taxes. No dodging them for this old guy.
If you do a visual survey around the ramps... almost all the RV's are parked flaps down. Reasons have been posted here.
I put my EXPERIMENTAL sticker on the upper part. Then it only shows to PAX boarding and not the rest of the time.... drift oops.
One of your challenges will be to slow down to flap operating range. We have fast little planes... but not much speed range on the flaps.
Since mine are electric and just a simple toggle... I often approach the field too fast on purpose. As I round out... I keep adding flaps until right before touch down. It does bump the workload up... since pitch forces are changing throughout the landing. But that just makes it fun and challenging.
Plus I like hearing the tower tell the guy in front of me to keep the speed up... RV to follow.
 
No flap approaches

Brad,

Re-trimming after flap deployment during a coupled approach is good, but I'm more concerned about departing from the glideslope than making the perfect landing (being a low time instrument pilot). If I were flying an approach to near minimums into a short runway I would definitely add flaps and re-trim. John
 
alpinelakespilot2000 said:
....I was originally taught the "always raise your flaps for taxi" when learning to fly a Cessna, but then I once had a really experienced instructor ask me, rhetorically, "why?" Neither of us could find a good answer to that. ....
Click to expand...

When I was learning to fly, I had an instructor who answered that question on a windy day. We were taxiing along in the Cessna 150 into the wind, not all that fast, and he abruptly dropped the flaps and hauled back on the wheel. We were at or just above idle power - and it was windy, remember. The airplane popped off the ground, stalled, and dropped back down.

Got my attention.

Dave
 
David Paule said:
When I was learning to fly, I had an instructor who answered that question on a windy day. We were taxiing along in the Cessna 150 into the wind, not all that fast, and he abruptly dropped the flaps and hauled back on the wheel. We were at or just above idle power - and it was windy, remember. The airplane popped off the ground, stalled, and dropped back down.

Got my attention.

Dave
Click to expand...
Sure. If the winds are 35-40 knots, or whatever it takes a 150 to get off the ground, some common sense would be in order. I could see that.
 
20% quite often

When I do touch in goes I leave in the first 20% during the landing and then give full power and takeoff. I end up using much less run way than waiting for full flaps to retract before shoving in the power. It actually is more fun give it a try
 
No Flaps or Flaps

For the most part I agree with Steve. What can I say I've got over 400hrs and 20 some odd years flying a Stearman and mind you there are no flaps on this aircraft. I also have an RV-6 which I love to death and a Navion that I learned to fly with my WWII fighter pilot dad. The Navion as well as the RV-6 I will always use flaps if they are available but as Steve has mentioned in high cross winds or on my nose use as little as your conferrable with. I will use 10 to 20 and will rarely use full flaps unless of course I wish to do a short field landing. But remember at full position you've exhausted everything when you've slowed the aircraft at the bottom of the white arc. Fy safe.
 
I always use flaps. In gusty conditions, add 1/2 the gust factor to your ref speed "over the fence speed + 1/2 the gust factor".
 
sblack said:
Why? Still don't see the purpose of doing that.
Click to expand...

Seat of the pants only but I find the RV6 much more stable in the flare in gusty conditions with the flaps up. I suspect that the gusts interact with the ground and flaps to cause a ballooning effect. The flaps are very close to the ground at touchdown forming almost a air dam that seems to exaggerate gusts.
 
rightrudder said:
During calm conditions, I can't see a reason not to use full flaps (short of no-flap landing practice). Less kinetic energy on touchdown, less chance of nose wheel shimmy (for us -A guys), easier on brakes, tires, etc.
Click to expand...

Flaps have ZERO influence on nose wheel shimmy. Touchdown speed when you let the nose wheel down does.

I land full flaps 98.736% of the time in my 6A. The only time I land flapless is in very gusting conditions.

My landings are full flaps, Zero throttle unless conditions warrant otherwise.
 
sblack said:
Why? Still don't see the purpose of doing that.
Click to expand...

My experience only. The hardest landings I have to make are when the wind is straight down the runway and gusting 30+. I hate that. Two things flaps do. 1. increase lift. 2 increase drag. The gusts comes, I balloon. The gust drops, I drop. With zero flaps this is affect is lessoned some.

Strong crosswind. Again the gusting 30+ 80 degree crosswind. A zero flapper for sure. If I used flaps the fact that the flaps are hanging down gives more area for the crosswind to grab, hence harder to compensate for. The gusts in this instance do not increase/decrease lift. An easier landing than straight down the runway gusts.

I really like challenging crosswinds. I loath challenging straight down the runway winds.

My $0.02
 
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Using extremes makes it easier to see sometimes. Imagine an airplane that lands at two hundred, versus one that lands at twenty. We have a twenty mile per hour crosswind. The two hundred m.p.h. plane goes forward 200 units for every 20 sideways, while the twenty m.p.h. plane goes 20 forward and twenty sideways. So, the angle the plane crabs while flying to maintain a track over the runway is different. The twenty m.p.h. plane is in a 45 degree crab. The 200 m.p.h. plane less than ten degree crab. To land, we transition from a crab to a slip by using rudder to push the nose to align with the direction of runway, so the tires are parallel with the direction we need to be going to land. The 200 airplane needs very little rudder imput to accomplish this. It is almost like the crosswind is non existent. The twenty m.p.h. plane takes a huge amount of rudder, and may not even have enough rudder imput to swing the nose that far! If we could have a way to just change the 20 m.p.h. airplane into a 200 m.p.h. airplane when we need that for landings. So, the point of this is two fold. One, the faster we can land, the less crab angle we have to overcome. If we are close to a speed where we are using full rudder and we get gusts on top of it, we might not have enough control to land. So, a no flap landing raises the stall speed slightly to allow us to touch down faster with less crab angle to remove with rudder! This is the control our airplane has to make it closer to the 200 m.p.h. plane. Secondly, the faster we go, the more force a deflected control has for a given imput. If we can land faster (stall at higher speed), the rudder won't need as much deflection to align the nose to the direction of travel necessary to land as it would at a slower speed. We have more control reserve, so to speak, at higher landing speeds! The rudder works on a lever arm back from the center of gravity of the plane. If you can make the plane land faster, less rudder imput is necessary for the force required to align the airplanes with the runway, and less change of angle is required too. If you move the center of gravity forward, your rudder has more authority too, because you lengthen the lever arm (another discussion)! Now, one last thing: remember, lift causes drag. After touchdown, the airplane still wants to weathervane towards the wind. Let's say we have a right crosswind. The plane wants to turn right. As we slow, the rudder runs out of enough force to keep the plane aligned with the runway. The plane is still light on the tires, so brakes don't work well either. If only we could have some way to pull backwards on the left wing till we get a little slower and the tires have enough friction to grip! We do, but most pilots quit flying after touchdown. Roll the ailerons full stop towards the wind after touching down. In this situation, the left aileron is down, causing lift and also drag. More drag on the left wing is free help to keep us aligned with the direction we want to go and not the way the cross wind wants us to weathervane and go! It is like giving the full left rudder we are holding just a little boost! Just some thoughts I hadn't seen up to this point..

jimmyB
RV-6
 
jpowell13 said:
I thought of one case where adding flaps can be a problem. When practicing coupled approaches my autopilot pitch servo gets overloaded due to out of trim condition when I add flaps. For that reason I may land without flaps after flying a coupled approach. John
Click to expand...

No need to worry. I've been told by several people here that the failure of an autopilot would never be a safety concern. :)
 
Interesting discussion. I've had my (bought) -7A less than a year, but my experience is that flaps on my plane add very little lift, mainly just drag. When going from no flaps to full flaps, the plane does not required any trimming, which tells me there's little additional lift. I always use full flaps landing except in strong, gusty crosswinds, because the drag from the flaps combined with the flat CS prop are like putting on speed brakes during the flare and floating is negligible, even at the fairly high approach speeds I use.
 
kstone said:
Interesting discussion. I've had my (bought) -7A less than a year, but my experience is that flaps on my plane add very little lift, mainly just drag. When going from no flaps to full flaps, the plane does not required any trimming, which tells me there's little additional lift. I always use full flaps landing except in strong, gusty crosswinds, because the drag from the flaps combined with the flat CS prop are like putting on speed brakes during the flare and floating is negligible, even at the fairly high approach speeds I use.
Click to expand...

Try 10 degrees of flaps for take off.
It does provide earlier lift not there at zero flaps.
 
A question for the experts. I fly my 6A from a field where most strong winds are 80-90* crosswinds from the South. There are a bunch of buildings and trees on the south side of the field that are about 100 yards away and for the whole length of the runway. I get a lot of unpleasant gusting, rotors, etc. When the winds are gusting >20-25, I get violent sinks of 5' or so while flaring. Due to this, I have dropped my SOP from 40 -> 30* of flaps.

I am wondering, will reducing flaps further help me to better manage these situations? It is a 4000' runway, so I have plenty of room to work with.

Thanks,

Larry
 
cool analysis

rv699jb said:
Using extremes makes it easier to see sometimes.

Imagine an airplane that lands at two hundred, versus one that lands at twenty. We have a twenty mile per hour crosswind. The two hundred m.p.h. plane goes forward 200 units for every 20 sideways, while the twenty m.p.h. plane goes 20 forward and twenty sideways.

So, the angle the plane crabs while flying to maintain a track over the runway is different. The twenty m.p.h. plane is in a 45 degree crab. The 200 m.p.h. plane less than ten degree crab. To land, we transition from a crab to a slip by using rudder to push the nose to align with the direction of runway, so the tires are parallel with the direction we need to be going to land.

The 200 airplane needs very little rudder imput to accomplish this. It is almost like the crosswind is non existent. The twenty m.p.h. plane takes a huge amount of rudder, and may not even have enough rudder imput to swing the nose that far!

If we could have a way to just change the 20 m.p.h. airplane into a 200 m.p.h. airplane when we need that for landings.

So, the point of this is two fold. One, the faster we can land, the less crab angle we have to overcome. If we are close to a speed where we are using full rudder and we get gusts on top of it, we might not have enough control to land. So, a no flap landing raises the stall speed slightly to allow us to touch down faster with less crab angle to remove with rudder!

This is the control our airplane has to make it closer to the 200 m.p.h. plane. Secondly, the faster we go, the more force a deflected control has for a given imput. If we can land faster (stall at higher speed), the rudder won't need as much deflection to align the nose to the direction of travel necessary to land as it would at a slower speed. We have more control reserve, so to speak, at higher landing speeds!

The rudder works on a lever arm back from the center of gravity of the plane. If you can make the plane land faster, less rudder imput is necessary for the force required to align the airplanes with the runway, and less change of angle is required too.

If you move the center of gravity forward, your rudder has more authority too, because you lengthen the lever arm (another discussion)!

Now, one last thing: remember, lift causes drag. After touchdown, the airplane still wants to weathervane towards the wind. Let's say we have a right crosswind. The plane wants to turn right. As we slow, the rudder runs out of enough force to keep the plane aligned with the runway. The plane is still light on the tires, so brakes don't work well either.

If only we could have some way to pull backwards on the left wing till we get a little slower and the tires have enough friction to grip! We do, but most pilots quit flying after touchdown. Roll the ailerons full stop towards the wind after touching down.

In this situation, the left aileron is down, causing lift and also drag. More drag on the left wing is free help to keep us aligned with the direction we want to go and not the way the cross wind wants us to weathervane and go! It is like giving the full left rudder we are holding just a little boost!

Just some thoughts I hadn't seen up to this point..

jimmyB
RV-6
Click to expand...
Very interesting points, Jimmy. I've always read "climb into, dive away from" when it comes to how to hold the controls when on the ground. That matches your suggestion.
 
lr172 said:
A question for the experts. I fly my 6A from a field where most strong winds are 80-90* crosswinds from the South. There are a bunch of buildings and trees on the south side of the field that are about 100 yards away and for the whole length of the runway. I get a lot of unpleasant gusting, rotors, etc. When the winds are gusting >20-25, I get violent sinks of 5' or so while flaring. Due to this, I have dropped my SOP from 40 -> 30* of flaps.

I am wondering, will reducing flaps further help me to better manage these situations? It is a 4000' runway, so I have plenty of room to work with.

Thanks,

Larry
Click to expand...

I had same experience at former home, Troy Airpark, one day with gusty cross wind. Sink at about 100' was very noticeable and with 40 could not control it, made go around several times. Finally tried it with 20 flaps and was able to fly through the sink and manage a landing.
 
kstone said:
Interesting discussion. I've had my (bought) -7A less than a year, but my experience is that flaps on my plane add very little lift, mainly just drag. When going from no flaps to full flaps, the plane does not required any trimming, which tells me there's little additional lift. I always use full flaps landing except in strong, gusty crosswinds, because the drag from the flaps combined with the flat CS prop are like putting on speed brakes during the flare and floating is negligible, even at the fairly high approach speeds I use.
Click to expand...

The OP was asking about landing his RV-9, which is significantly different than your RV-7A. The -9 with its high lift / aspect ratio wing and follower flaps is significantly different than a -7(A).

As you read these replies, pay attention to the airplane listed in the signature sector the commentators.

With the -9, you want drag and must nail the approach speed (especially with a FP prop).
 
N941WR said:
The OP was asking about landing his RV-9, which is significantly different than your RV-7A. The -9 with its high lift / aspect ratio wing and follower flaps is significantly different than a -7(A).

As you read these replies, pay attention to the airplane listed in the signature sector the commentators.

With the -9, you want drag and must nail the approach speed (especially with a FP prop).
Click to expand...

In the interest of clarity regarding details of the RV-9, it doesn't have follower (or fowler) flaps. It has slotted flaps.
Fowler flaps deploy on a track system (think Cessna) that moves the flaps aft for an increase in wing area before they actually start to deflect much.

I do agree with the rest though......
 
Landing

This has been a very good read and enjoyable.Here is my short take away from this learning. There are many types of pilots and many different ways of landing said airplane and a factor is how many people are watching , the more people the better chance of screwing up like at a fly-in I know that's in the back of your mind and no one said anything about it. The other main factor is every landing is different ! As guy who flew a champ for 33 years and all the Cessnas and high performance twins that came over the fence at 125 mph and Stearmans I can say an RV is one of the easy airplanes to land I have ever flown.My RV6 is very forgiving I have my trim set for cruise and never touch it unless its to adjust for different weight in cruise.One day I may build a new left elevator with no trim tab and use a spring system like the aileron .Now anybody that's having a problem landing cover up your airspeed and let the stick tell you how fast your landing no need to look at airspeed after the flaps are down on final.Pick a point on runway and try to land on it every time.Its like the old cropduster told me (you cant use runway behind you.)
Bob
 
Sinks like a rock?

Several posts here talk about coming over the fence below ## kts and anything below that it "Sinks like a rock (SLAR)".

What is missing from the general statement is if at idle power or not, solo or gross weight. CS or FP prop is also a factor in this statement.

My RV7A (CS prop) SLAR below a certain airspeed with full flaps at idle power but if I carry a little power I can land slower. I typically pull the power back to idle once over the numbers so I never let the speed drop below my "SLAR" speed until I am only a foot or two over the runway.

It would interesting to note the what SLAR speeds at idle the previous posters are experiencing.
 
As Bill eluded to, there is a considerable difference between the performance of the 9 compared to the 6,7,8. Exceedingly so if it has a fixed pitched prop. The 9, whether little wheel on the tail or nose, does not 'drop like a rock' at idle. Slowing a fixed pitched prop 9 down takes quite a bit of planning and execution. I would say that slowing the plane down was the most difficult part of learning how to fly my 9A. Get the speeds right and it will land itself. Too fast, you will never land. Too slow, well, the only too slow is below stall. Get below stall and it does come down like every other bird, but then, who wants to get below stall before the wheels touchdown?

Live Long and Prosper!
 
Aircraft type

A).

As you read these replies, pay attention to the airplane listed in the signature sector the commentators

Not sure how to highlight the quote from a previous post but the above was said. I think it is nice when people put their aircraft type in their actual post. I have had times when I read a question, saw no aircraft type, looked at the signature and still did not know the aircraft type. I think it is a good habit to mention the aircraft type in the post so everybody knows what the real question is.
 
rvbuilder2002 said:
In the interest of clarity regarding details of the RV-9, it doesn't have follower (or fowler) flaps. It has slotted flaps.
Fowler flaps deploy on a track system (think Cessna) that moves the flaps aft for an increase in wing area before they actually start to deflect much.

I do agree with the rest though......
Click to expand...

Thank you for correcting me Scott! Much appreciated.
 
FLY6 said:
A).

As you read these replies, pay attention to the airplane listed in the signature sector the commentators

Not sure how to highlight the quote from a previous post but the above was said. I think it is nice when people put their aircraft type in their actual post. I have had times when I read a question, saw no aircraft type, looked at the signature and still did not know the aircraft type. I think it is a good habit to mention the aircraft type in the post so everybody knows what the real question is.
Click to expand...
thanks for the suggestion. I have made the change to my signature.

Also, as an FYI, there are a few ways to quote something. If you wish to quote the entire post just click on the word QUOTE at the bottom of that person's post. If you want to quote more than one post click on the quotation marks at the bottom of their post until the last person you wish to quote. Then on that last one click on the word QUOTE. IF you only want to quote part of what they said just delete the words out from between the QUOTE tags. Or, you can cut and paste words in a quote by copying them then clicking on the 'quote' button above your post in the toolbars. It is the button that looks like a little cartoon QUOTE bubble with words in it.
 
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Also, as an FYI, there are a few ways to quote something. If you wish to qutoe the entire post just click on the word QUOTE at the bottom of that person's post. If you want to quote more than one post click on the quotation marks at the bottom of their post until the last person you wish to quote. Then on that last one click on the word QUOTE. IF you only want to quote part of what they said just delete the words out from between the QUOTE tags. Or, you can cut and paste words in a quote by copying them then clicking on the 'quote' button above your post in the toolbars. It is the button that looks like a little cartoon QUOTE bubble with words in it.[/QUOTE]

Thank you, good to learn something new even if it not airplane related.
 
FLY6 said:
Also, as an FYI, there are a few ways to quote something. If you wish to quote the entire post just click on the word QUOTE at the bottom of that person's post. If you want to quote more than one post click on the quotation marks at the bottom of their post until the last person you wish to quote. Then on that last one click on the word QUOTE. IF you only want to quote part of what they said just delete the words out from between the QUOTE tags. Or, you can cut and paste words in a quote by copying them then clicking on the 'quote' button above your post in the toolbars. It is the button that looks like a little cartoon QUOTE bubble with words in it.

Thank you, good to learn something new even if it not airplane related.
Click to expand...

Looks like you almost have it except it appears you deleted the beginning quote tag. If it had not been deleted your post would look similar to mine above where I quoted your post. Remember both beginning and ending bracketed tags have to be there or it breaks.
 
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Pmerems said:
Several posts here talk about coming over the fence below ## kts and anything below that it "Sinks like a rock (SLAR)".

...

It would interesting to note the what SLAR speeds at idle the previous posters are experiencing.
Click to expand...

Keep in mind that each aircraft has its own individual airspeed errors, as does each ASI. Two RVs in close formation, at the exact same airspeed could easily have ASI indications that differ by 5 kt, or more.

The final approach airspeed that works perfectly in one RV may be dangerously slow in another RV.

Go flying early in the morning, or late in the evening, when the winds are calm and the air is smooth. Fly a series of approaches, decreasing the speed by a kt or two each time. Note the slowest approach speed that allows a safe, acceptable flare and touchdown - this is the minimum safe speed - don't ever, ever let the speed get slower than that. Add 5 kt to the minimum speed to find your normal target approach speed. The 5 kt allows a bit of margin for typical speed variation in light turbulence, pilot inattention, etc. If the day is particular gusty, add a bit more speed, to ensure that the lowest speed stays above the minimum speed you found.
 
Tailwheel RV7. I generally use full flaps on landing. However, if I'm landing because of a line of storms about to hit, there is no telling what kind of wind will happen. I know, don't go near them, but in the South they are everywhere in the afternoon. Anyway, the ATIS or AWOS wind report won't give you the story, and if I know I'm near the gust front, the flaps will be up. Why? It increases the effective wing loading, (even though they're not fowler flaps that increase area), and gives better penetration, since the wind gusts are a lower % of the landing speed.

After getting one main wheel down, I want to push the nose way down to hold it there. If the crosswind is bad, of course, you have to wait a while to get the other main on, but when you do, you've got brakes to help hold it straight while slowing down. When you have to let the tail down, it's much slower, well below stall speed.

I'm one of those people that imagines the load on the flap motor as I'm deploying them, so I generally wait until I'm about 80 kts or less to reduce the load. These planes handle well in landing, and on a normal windy day, I'd still stick with full flaps.
 
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