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High speed flap deployment damage

647jc

Well Known Member
Curious if anyone has ever damaged the flaps on an RV by deploying at too high of speed. This question would apply mostly to electric flap systems. I know many people think or assume the flap motor will stall or blow a breaker before damage to flaps would occur but I don't necessarily buy that. Also, the flaps on some RV models are much larger than others, the 9 flaps are huge compared to a 7 or 6 and would require more effort to deploy at high speed but would also be more susceptible to damage. I don't think this was as much a problem with the simple Vans toggle switch contol since you had to continue holding the switch to drive the flaps down but with the newer flap controllers, a single tap of the switch or button will send the flaps to the first notch position and an accidental tap of that switch, especially when mounted in the stick grip, is fairly easy to do.
 
Watch it. Pay attention if you think the plane is not behaving.

Don't put the flaps on the stick. You will find other recommendations to put it next to the throttle. Good idea.

That said I have not deployed at high speed, but I have tried to fly with full flaps down :rolleyes:. I just could not seem to get up to speed. When I inspected the flaps for damage I found that the push rods had been vibrating and showed signs that they had finally contacted with the fuselage. Yes I did feel the plane was flying rather roughly. I am an idiot and... was distracted and... I landed flaps up just in case after I caught on to the problem. Later I purchased the more heavy hex profile rods but have not put them in yet. I don't really see any problem, but I have friends that point out everything I do wrong. They are most helpful in making me a better pilot. They remind me everytime we meet, so that I remain a good pilot :( I see no real problem with the current flap design. I think the only failure I have heard of is where the rods were bent or threaded so that the rod bearing actually poked out the side or some other obvious construction error. I think there was an issue where the hinges were bad, again something that should be obvious.

Good design Vans. The flaps seem pretty bullet proof to me.
 
Not knocking what you did - you know the circumstances and I don't. As a general rule, though, if you exceed the limit on something, leave it where it is, reduce below limit speed and land in that configuration. If something had got damaged and you then move it.......

Having said that, when you realise you have exceeded a fllap limit, it's very difficult to resist the urge to whip them up!
 
You are so right.

Not knocking what you did - you know the circumstances and I don't. As a general rule, though, if you exceed the limit on something, leave it where it is, reduce below limit speed and land in that configuration. If something had got damaged and you then move it.......

Having said that, when you realise you have exceeded a fllap limit, it's very difficult to resist the urge to whip them up!

You are so right I should have left everything alone. I did fly another hour or so after I put them up. There was not much choice. I was on top and did not have alll the usual choices. I never considered leaving the flaps down. I was just sort of annoyed with myself more than anything. Good point on messing with things. I will remember this good comment.. and thanks.
 
Perception & Perspective

Curious if anyone has ever damaged the flaps on an RV by deploying at too high of speed. ......newer flap controllers, a single tap of the switch or button will send the flaps to the first notch position and an accidental tap of that switch....is fairly easy to do.
I found your comments interesting and spoke to a perspective that forced me think beyond my own experience when it comes to flap management or control. You ask is anyone has ever damaged the flaps on an RV by deploying at too high a speed. Probably. In my experience, however, the chance of that happening is unlikely, even improbable. That is because the airplanes I am most familar with have been fitted with a momentary switch to control the flaps. On my Cessna 150, the (momentary) flap toggle was located on the instrument panel. On my RV's, the (momentary) flap toggle is located on the joystick grip. Because this is so, it is highly unlikely a pilot would activate and intentionally HOLD the flap switch down long enough deploy the flaps beyond a few degrees of deployment. Beyond that, flap deployment serious enough to risk structural damage would have to be intentional act. Heck, the unexpected pitch change alone should alert even the most clueless pilot! That leads me to ask the following question and I don't mean to sound at all flippant about it....just curious. What is so wonderful about a flap controller? Here's the scenario: You are flying the pattern and slowing to land. Somewhere on downwind or base you find your airpeed about 115 MPH. You would like to slow down to Vfe (100 MPH) as soon as possible to make a normal flap landing. With the momentary flap switch, all you have to do is "tickle" the flap switch to deploy 2-3? of flap and that excess airspeed will quickly bleed down to Vfe. Alternatively, a flap controller gives the pilot no such option. No doubt, a flap controller holds a rightful place in aviation. Some airplanes are better served with one. But we are flying lightweight RV's here. We wear it as much as we fly it. Same scenario only this time the RV is fitted with a flap controller. Activating it, the pilot must accept a minimum of 10? of flap deployment take it or leave it. So again I ask...when it comes to flying RV's, what is so wonderful about a flap controller?
 
Probably distracted by having to look at your flap switch to find it next to the throttle cause its not on the stick where is should be :)
 
I did a night formation takeoff once on the wing, off grass, full flaps down. I was over ~130kts 2k'agl before I realized it. My normal pre-scan for form takeoff was different as I was struggling to see my leads configuration before the departure roll. Wx was crappy. We debriefed it as shame on both of us for not scanning pre roll just like we always would, even though we could see very little on each others plane. We should have taken extra time. Too focused on other unusual conditions that were going to demand our attention. Shame on us.

While I dont know if my flap motor will deply to full at that speed, the system will hold it on my plane without damage. I do have the hex rods.

As a note, I routinely drop ~15deg at 120kts to slow her down. I tend to come in high and hot into a pattern for safety and keep it close in or go initial.

Best
 
Split Flap

So again I ask...when it comes to flying RV's, what is so wonderful about a flap controller?

I agree. If you have ever experienced a "split flap" situation where only one side deploys, the last thing you need is a flap controller.

John Clark ATP, CFI
FAA FAAST Team Member
EAA Flight Advisor
RV8 N18U "Sunshine"
KSBA
 
Hmm..

I agree. If you have ever experienced a "split flap" situation where only one side deploys, the last thing you need is a flap controller.

Then all you need is a flap assymetry computer hooked up to each flap and the flap controller to prevent this :rolleyes:

Oh yea and while we're at it why not add a take off warning system so we don't take off with them at 40 deg
 
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I found your comments interesting and spoke to a perspective that forced me think beyond my own experience when it comes to flap management or control. You ask is anyone has ever damaged the flaps on an RV by deploying at too high a speed. Probably. In my experience, however, the chance of that happening is unlikely, even improbable. That is because the airplanes I am most familar with have been fitted with a momentary switch to control the flaps. On my Cessna 150, the (momentary) flap toggle was located on the instrument panel. On my RV's, the (momentary) flap toggle is located on the joystick grip. Because this is so, it is highly unlikely a pilot would activate and intentionally HOLD the flap switch down long enough deploy the flaps beyond a few degrees of deployment. Beyond that, flap deployment serious enough to risk structural damage would have to be intentional act. Heck, the unexpected pitch change alone should alert even the most clueless pilot! That leads me to ask the following question and I don't mean to sound at all flippant about it....just curious. What is so wonderful about a flap controller? Here's the scenario: You are flying the pattern and slowing to land. Somewhere on downwind or base you find your airpeed about 115 MPH. You would like to slow down to Vfe (100 MPH) as soon as possible to make a normal flap landing. With the momentary flap switch, all you have to do is "tickle" the flap switch to deploy 2-3? of flap and that excess airspeed will quickly bleed down to Vfe. Alternatively, a flap controller gives the pilot no such option. No doubt, a flap controller holds a rightful place in aviation. Some airplanes are better served with one. But we are flying lightweight RV's here. We wear it as much as we fly it. Same scenario only this time the RV is fitted with a flap controller. Activating it, the pilot must accept a minimum of 10? of flap deployment take it or leave it. So again I ask...when it comes to flying RV's, what is so wonderful about a flap controller?

Well said, Rick. Electronics that gets in the way of positive pilot control is asking for trouble. In my opinion, electronics should inform the pilot of a condition, not take independent action.

In the case of flaps, I have a Vfe alarm hooked to my flap limit switch. This warns me when above Vfe with the flaps out so that I can take action (if I want). It's an electronic gizmo, and it does not have to be perfectly functional for safe flight, unlike a flap positioning system.

"Red light comes on, push button, get a banana" (quote from an Airbus pilot).

V
 
Bells and whistles

Then all you need is a flap assymetry computer hooked up to each flap and the flap controller to prevent this :rolleyes:

Oh yea and while we're at it why not add a take off warning system so we don't take off with them at 40 deg

Yup, heaven forbid that you might have to turn your head and look at the flaps. The take off warning system needs to have a really obnoxious horn and a lot of microswitches that get out of adjustment. While we are at it we should hook the whole thing through the air data computer...;) I've been there, done that, and passed the checkride. The KISS principle rules!


John Clark ATP, CFI
FAA FAAST Team Member
EAA Flight Advisor
RV8 N18U "Sunshine"
KSBA
 
With mechanical flaps there is no way with the amount of muscle that I to deploy the flaps unless the plane is slowed down first.
 
Safeguards and overrides

In my opinion, electronics should inform the pilot of a condition, not take independent action.

I'll decline to debate that opinion... but I will point out that those are not the only two possible roles that electronics could play in this equation. Another role of particular relevance to this topic is:

Passive safeguard. The electronics don't take independent action, but they do prevent the pilot from taking an action that would jeopardize the integrity of the airframe (such as commanding a flap deployment above Vfe).

And if you feel that you as the pilot must have final authority over the electronics, then you can build in an override function. That's reasonable enough. Have it require the pilot to flip an override switch or some other such positive action to say "yes, for whatever reason I really do want to take actions that I understand are ordinarily not advised, so don't block me now".

So you still have full authority available if you ever need it under some special circumstance, but you now have a safeguard against accidental actions that you would want to prevent under normal circumstances.
 
flap overspeed

Sometime last winter, within my first couple of months of having the -8A, I was doing various practice maneuvers. After a power-off stall recovery, I failed to raise the flaps. I only noticed this after accelerating to about 130kts and after doing a couple of rolls!

I was a bit worried at the moment about what kind of damage I might have done. Nevertheless, the flap system continued to operate normally, and post-flight inspection was entirely normal.
 
When i fly IFR appoachs My airspeed is stabilized at 80kts at about 2000 rpm in the Skyhawk and I find that 1500 rpms in the 9A puts me in the 85 kts range.So its just about automatic to slow to 1500rpms and let the airspeed bleed down close to the airport (2 miles)with 10 deg flap on downwind 20 turning base full flaps on final with then a adjustment to the throttle based on the winds and my AGL. I grant U sometimes life is not always fair. But it does pretty much take the worry out of Vfe doing it like a IFR approach.
 
I used the Infinity stick grips so my flaps on a momentary toggle on the stick and I was concerned about myself or a passenger inadvertently deploying flaps in-flight. The Advanced flight AOA pro solved that issue with an audible warning when the flaps are deployed to a specified level.

I installed the pressure switch to call out "Flaps" (only once) when ever the flaps pass the 5 degree point. It's just slick! Also the little doughnut comes on the screen at that point so I have a visual reference as well.

- Peter
 
I did a....takeoff once....full flaps down....
Some 5 years ago and as a newbie with very few RV hours logged, I was still working off the 25 hour Phase One and sitting in an airport restaurant with a group of pilots including veteran RV-7A owner Dave Domeier. After the obligatory round of congratulations made its way 'round the table, Dave, seated next to me leaned in and quietly asked, "Have you taken off with the flaps down yet?" I had to smile as I recalled my recent experience, how very quickly the RV bounded into the air when I took off with 40° of flaps! This "right of passage" may compete for top billing with something else many builders have experienced...the double dimpled hole. :)
 
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I did that too...

Hi Rick

I did the same recently (during my 25 hour test phase). I was doing circuits in very light x-wind on my private field.....I would land, roll out, turn around and take off in the direction i just landed. I had an experienced RV pilot sitting next to me and he saw it coming when I forgot to retract the flaps after the turnaround......he chose not to comment to teach me a lesson. Off I went - as you said she jumped in the air pretty quick but in the climb there was no way she was going to accelerate through the flap speed limit. Learnt my lesson (and my mate had a good laugh).....I won't do that again and now make a habit of visually looking at my flaps prior to departure.

On top of that I'll support Pete's comment about the AFS AOA. I installed mine with a flap sensor switch to do the same. I have my flap selection switch on the stick but have also installed an isolator on the panel. If the isolator is left live and you accidentally bump the switch a rusty female voice squawks out "Flaps" with the first stage which will quickly remind you to retract them if you are exceeding the appropriate speed. It is an excellent feature.

Cheers,

Jon
 
There have been many comments regarding potential for flap subsystem damage if using a flap positioner above Vfe, given a momentary, inadvertent switch actuation. But doesn't it stand to reason that there are really three different Vfe values, one for each flap setting? The flap positioners I'm familiar with are set up for 10, 20, or 40 degrees of flaps IIRC.

Even though these values are not published, if you can have full flaps at 40 degrees & 100 kts, doesn't it stand to reason that you can have <40 degrees over 100 kts? Flap aerodynamic loads are certainly a function of indicated airspeed & flap angle, so in reality there is some curve relating these three, not the two we are taught (angle is ignored for simplicity).

I submit that the speed where damage might occur for the first "notch" of flaps (10 degrees, or what your flaps would try to get to with inadvertent switch actuation) is MUCH higher than Vfe, and might even be as high as normal cruise speed.

I would love to see Vans publish a Vfe for 10 degrees of flaps.
 
I know without a doubt that a 180hp RV7 with a FP Sens. prop can and will exceed Vfe in a full power go around climb executed from 55-60kts and full flaps if you are not watching it. It can do it quite easily actually.

Happend to me when my flap motor popped the fuse and it just happened to be at the same time I was executing a go around during some of my first flights. I ended up pulling off some power and climbing at a pretty steep angle to keep the speed down.

It actually took me by surprise that these things have that much excess power available. I was used to flying a 172 around wide open with full flaps and not gaining much if any speed.
 
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Even though these values are not published, if you can have full flaps at 40 degrees & 100 kts, doesn't it stand to reason that you can have <40 degrees over 100 kts?

Actually these numbers WERE published. Originally the RV-3, -4, and -6 with manual flaps were 2 position. Flap speed for 20* flap is 110 mph, 40* is 100 mph.
 
There have been many comments regarding potential for flap subsystem damage if using a flap positioner above Vfe, given a momentary, inadvertent switch actuation. But doesn't it stand to reason that there are really three different Vfe values, one for each flap setting? The flap positioners I'm familiar with are set up for 10, 20, or 40 degrees of flaps IIRC.

Good point Noah. For the 9, Vfe is listed as 90 mph and I remember reading somewhere up to 10 degrees deployment was ok up to 100 mph. Keep in mind the flap size on a 9 is substantially larger than a 6 or 7 and the maximum angle of deployment is 30 degrees not 40 as on other models.

I also remember reading (not sure if factual) that the original Vfe for the 9 was 100 mph, even the early airspeed indicators provided by Van had a white arc starting at 100 mph. The Vfe was later lowered to 90
because they found many of the flap motors could not fully extend the flaps to 30 degrees at 100 mph, they
either stalled or poped a breaker so the Vfe was lowered to 90. Perhaps an early 9 builder could confirm this.

Anyway, my sequential flap controller has it's buttons mounted on the panel so an inadvertent push of the
'down' button is not likely and if it does happen, the system will only go to the first position which is 10 degrees and then stop. Also, I can abort any positioning command by simply pushing the opposite button and the flap motor will stop dead in it's tracks, not sure all controllers will do this.

This has been a very interesting and informative discussion, I think the bottom line is that the RV flap
systems are quite robust and damage to them from an inadvertent high speed deployment is not very likely although it is not recommended.
 
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Hi all,

Just to add that I have now taken off twice with flaps at 18 degrees (my stage 1 position) and forgotten to retract them. The first time I got to 120 kts and the second time, I got to 130kts. I can not see any damage as such, but I think that one flap may now be slightly twisted. I may have to derivet the end rib, straighten and re-rivet before I paint.

I think I will have to invest in that flap-airspeed warning system...
 
Checklist usage

From some of the comments one could conclude that checklist usage isn't very rigorous. Being a product of the Viet Nam era military where we didn't let an aerial fart without a checklist perhaps I'm a bit out of synch with the current civilian protocols. I have a dirt simple Steen Skybolt with throttle, mixture, prop and trim but I use a checklist/callout for before takeoff, after take off and before landing. Do I really need it? Maybe not but it helps maintain my discipline and mitigates my natural tendancy to forget stuff.
Don
 
From some of the comments one could conclude that checklist usage isn't very rigorous. Being a product of the Viet Nam era military where we didn't let an aerial fart without a checklist perhaps I'm a bit out of synch with the current civilian protocols. I have a dirt simple Steen Skybolt with throttle, mixture, prop and trim but I use a checklist/callout for before takeoff, after take off and before landing. Do I really need it? Maybe not but it helps maintain my discipline and mitigates my natural tendancy to forget stuff.
Don

I'm with you on this one Don.:)
 
From some of the comments one could conclude that checklist usage isn't very rigorous. Being a product of the Viet Nam era military where we didn't let an aerial fart without a checklist perhaps I'm a bit out of synch with the current civilian protocols. I have a dirt simple Steen Skybolt with throttle, mixture, prop and trim but I use a checklist/callout for before takeoff, after take off and before landing. Do I really need it? Maybe not but it helps maintain my discipline and mitigates my natural tendancy to forget stuff.

Before takeoff.................I have a short abbreviated checklist, which includes the important items, but without a lot of detail...........and those certain items I've overlooked in the past.... such as both fuel caps in place, transponder on, canopy closed and locked, etc. This list is about 2 1/2 by 8" in size and laminated. Very convenient!

L.Adamson --- RV6A
 
Checklists are important but there are some things that should come instinctively, like pushing the throttle up for take and retarding it for landing.

I have flaps on a checklist before take off but after take off they come up at or before 80 knots - no checklist. That has to be a standard procedure like raising the gear on a retractable airplane. By the time you remember to use a checklist, they could be off the airplane.
 
Yes check list would be good and I have one but unfortunately it seems I need a check list to check my checklist... Sorry just human here and got caught up in the moment of 'engine is no longer running like bag of bolts...'
 
Why is my RV only getting 118kts indicated at 22sq?

I should have know when I increased the throttle and started my takeoff roll when I gave a little stick forward and hmmmm....that seemed like it took very little pressure.

Ok, out of the patch I go!

Climb out was normal as I climbed quick and held 80 knots to try to get my oil temp up to 180 on purpose....since I struggle in the cold weather to see higher than 160.

Now the level off and throttle back. I set about 22 MP and 2250RPM. Airplane starts to accelerate and then peters out at 118kts! :confused:

What the heck is going on?

I look around at the gauges and the a quick look outside and see 1 notch of flaps! :mad:

So, I slowed up raised the flaps, pour the coals to it again and gee....I have an RV again :D

I realized when I did my flight control check at the end of the runway I bumped my flap momentary switch and they ran to half flaps. Checklist works good, but my fat thumb got in the way on this one.

My flap switch on my Infinity Grip is momentary down, OFF in the middle and UP command locks in the up position. I get picky on keeping my flap switch in the middle position at all times. NOT anymore! I will now keep it in the Full UP position and not neutral (OFF) for flight.

Ops check and visual after landing all good.
 
I will now keep it in the Full UP position and not neutral (OFF) for flight.

Ops check and visual after landing all good.

There are no limit switches to shut off the motor.
If you do this without some type of flap controller in the system (it doesn't sound like you have one) your flap motor will be running any time the flap switch is in this position.
This will likely significantly reduce the life of the motor.
 
Good thought Scott.

I have a VP100 which controls the up, down, neutral. All the values are set within that box for up, down and intermedient limits.

When I was building someone suggested I change ut my switch to momentary up and down since the VP100'controls it all.

Since I had just assembled my Infinity Grips I thought no way am ai going through that! I'll just live with the "inconvenience" of having to always move the switch from up to neutral.

Well, after this event I am glad I can leave the switch "locked" in the up position.

Thanks for the input though....I won't want to burn the motor up.
 
...just curious. What is so wonderful about a flap controller? Here's the scenario: You are flying the pattern and slowing to land. Somewhere on downwind or base you find your airpeed about 115 MPH. You would like to slow down to Vfe (100 MPH) as soon as possible to make a normal flap landing. With the momentary flap switch, all you have to do is "tickle" the flap switch to deploy 2-3? of flap and that excess airspeed will quickly bleed down to Vfe. Alternatively, a flap controller gives the pilot no such option. No doubt, a flap controller holds a rightful place in aviation. Some airplanes are better served with one. But we are flying lightweight RV's here. We wear it as much as we fly it. Same scenario only this time the RV is fitted with a flap controller. Activating it, the pilot must accept a minimum of 10? of flap deployment take it or leave it. So again I ask...when it comes to flying RV's, what is so wonderful about a flap controller?

Not all flap controllers made equal, And here is my bragging about FPS :D

My first notch which I can set it at any angle is only about 5 degrees. I can and have set it at times when my speed is above the Vfe (100-105k) without any issues. I also have a separate and momentary switch which operates like the basic model, the flaps get deployed as long as you are holding the switch down, the best of two world.

Now to the positives, I my elevator trim gets set for each notch of flap and in a touch and go situation, all I need is to hold the button for a second longer and the flaps gets retracted all the way up.
 
There are no limit switches to shut off the motor.
If you do this without some type of flap controller in the system (it doesn't sound like you have one) your flap motor will be running any time the flap switch is in this position.
This will likely significantly reduce the life of the motor.

That is true about the motor not having internal limit switches Scott, but almost everyone I have seen that uses the Infinity stick switch for flaps adds an "up" limit switch to the actuator - it is simple, well documented (lots of pictures here and on web sites), and folks were doing it long before I built my -8.

You are right that you really MUST have an up limit switch if you keep the stick switch in the "up" position, and I think you'll find that most folks do. Good warnign for those who haven't thought this through.
 
There are no limit switches to shut off the motor.
If you do this without some type of flap controller in the system (it doesn't sound like you have one) your flap motor will be running any time the flap switch is in this position.
This will likely significantly reduce the life of the motor.
+1 on this comment. It would not be a wise decision to leave the flap switch in the UP position and have the flap motor running continuously during flight. That would make for a short life on that motor. I have the same setup as described and I will NOT leave the switch in the UP position because the motor will continue to run.

I have recently purchased a limit switch to install for this reason. Plan on getting it installed as soon as I can find a time to stop flying the airplane long enough to pull the panels off of the flap area to do so. In the meantime, I remain very diligent to raise flaps as soon as the plane shows it is exhibiting positive climb out. I then look out the window to verify flaps are fully up, then flip the switch to the middle OFF position.
 
Anyone have experience with the flap limit circuit shown below?


303dbua.jpg
 
Flap sensors

I saw only one post that hinted at possible damage due to HS deployment making it pretty low on my list of concerns but I have seen many comments over the years about dead flap motors.

I have recently purchased a limit switch to install for this reason. Plan on getting it installed as soon as I can find a time to stop flying the airplane long enough to pull the panels off of the flap area to do so. In the meantime, I remain very diligent to raise flaps as soon as the plane shows it is exhibiting positive climb out. I then look out the window to verify flaps are fully up, then flip the switch to the middle OFF position.

I prefer sealed or non-mechanical contact sensors such as reed switches, magnetic angle sensors and current sensors over micro switches. In my aircraft, electronics can turn off the motor on travel limits or a motor stall covering not only leaving the switch on but also detecting the heavy load of HS deployment.
 
I have 2 Ray Allen switches side-by-side. One for flaps and 1 for trim. Both have pullable breakers below them. It only took one time of pressing the wrong one before pulling the flap breaker prior to takeoff was part of the pre-takeoff checklist.
 
I lost 2 friends in a Twin Bee because the flap and gear levers were identical and side by side. There's a reason some knobs are shaped like a flap, some like a gear, and some like a little wheel.
 
Fessin' up ....

Again, some of these posts are so timely they just blow my mind. Just last Friday I was on flight #10 in my fly-off period and was at another airport within my legal area. I was there to do a GPS taxi test to see how close the the GPS direction matched my EFIS ... Which has not been calibrated yet. I got fully distracted with all the directional tasks and departed unknowingly with full flaps. yes, several obvious signs were there, but I was both alarmed and puzzled by the fact I could not get RPMs above 2300 on climb out, nor could I get the A/S to its normal point. Finally realized after quite awhile that the flaps were out. I saw 116kts max during my boneheaded episode. I did a full inspection after landing and can find no damage of any kind .... Everything looks and operates as normal. it appears I have Vans to thank ... Their design Must have boneheads like me in mind. :eek:
 
Flap-alarm..................

I have a Dynon EFIS and EMS. I have always wondered why there is no way to set a "flap overspeed alarm"..........
Since the EMS knows the position of the flaps and the EFIS knows the airspeed, it should be very simple to set an alarm at a certain speed for each of the flap settings, to let us know that we are flying to fast. This will work in all directions:
  • Landing to fast with flaps selected.
  • Forgotten flaps on take-off.
  • Unintentionally actuated flaps during flight.
  • Run-away flap motor.
  • Creeping down flaps during flight.
  • I guess you can think of some more...........
Dynon are you reading this ?

Regards, Tonny.
 
Flap Deployment at high speeds...

If I try and pull full flaps in my 4 with the strong arm flaps and slightly worn notches on the side of the seat, the flaps just pop off again. Its like an inadvertently built in safety system!!

Joe Hine
C-FYTQ RV4
 
+1 on this comment. It would not be a wise decision to leave the flap switch in the UP position and have the flap motor running continuously during flight. That would make for a short life on that motor.
Soooo, i have a confession to make, just a few short hours after posting about leaving the flap switch in the UP position, this afternoon my wife and I flew to the in-law's for Thanksgiving. I can now answer just how short a life the flap motor will have when left in the UP position on the Infinity grip. That would be about 1.5 hours. On a 1.9 hour flight that was how long it ran before it fried itself completely. After posting a warning about this I go and do that very thing I posted not to do. Not sure why but I must have gotten distracted when I raised the flaps and consequently I failed to flip the switch to the OFF position. About half way through the flight I thought I smelled hot grease. I could not fathom where the smell was coming from. Did not even consider the smell was associated with the flaps, that is until the second I started to deploy flaps in the pattern and saw nothing happening. I suddenly realized where the hot grease smell was coming from. Landed with no flaps and I guess I will get to do so again on the flight home. DOH! What a bonehead move!

Well now there is no question as to when I will finally be installing that limit switch, along with a new flap motor! :(
 
New flap motor...

Contact Brad at Usher for the motor. I just bought one and he was great to work with.

[email protected]
503-992-0015

$125 plus shipping. He sent it priority mail the day after he got my CC info. Packed in packing material in a box, then that box packed in packing material in another box!! Shipped from OR on a Thursday, arrived in FL the following Tuesday.

Installed and working perfectly.
 
Originally the RV-3, -4, and -6 with manual flaps were 2 position. Flap speed for 20* flap is 110 mph, 40* is 100 mph.

110mph for 20deg on the 6 ? Are those #s confirmed or published by Van's ?

If so, you just made my day :)

I was told not to touch the flaps before getting down to 100mph on my 6A. I never liked the nose high atitude I had at 100mph with no flaps... so I'll be glad to drop a notch at 110mph from now on!

What do you guys think of a 5-10deg flaps setting at 120mph to help it slow down?
 
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At a 120 mph, just pull back a little on the stick. It will slow right down. You do have the power pulled back....................?
 
Flaps

Configuration: Many different styles.

Mine is simple and effective:
1) Momentary (up-off-down) switch mounted on dash next to throttle so my thumb can reach it when hand is on throttle. (Preferred configuration)

2) Limit switches prevents any unwanted issues. (Worth the effort)

I like this dash mounted setup next to the throttle much better in my -7 than my stick mounted system that was on my -6. The stick mounted flap setup with momentary micro switches was irritating when landing in turbulence. This is the opposite of what I though would be my preference. Turbulence was the issue.

-No degree indicator needed on an RV. Just look out the window to confirm after counting. It takes 8 seconds to cycle the flaps. Simple.

-Don't use flaps for T/O and no over speed issues happen.

-If tower calls go-around, most RV's can handle the traffic pattern speed, (110) with half flaps, including climb. RV's are wonderful.

I have heard of people having flaps out at over flap deployment speed. No damage reported. If excessive over speed with flaps it may damage them. Just repair or build some new ones then you won't do it again.
 
My son is 6ft. 5 inches tall and on a long cross country flight in my RV-8 he stretched out his long legs up beside me in the front seat. I was cruising along at 155 knots and the airplane felt like it stopped in mid air. Took a minute or so to figure out that his foot was on the flap switch and they had deployed 40 degrees. I retracted the flaps and landed. Did an inspection and found no damage. I do have the stronger hex flap rods installed. I don't let anyone stretch out their legs anymore. Bill.
 
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