VAF Forums

VAF Forums (https://vansairforce.net/community/index.php)
-   Safety (https://vansairforce.net/community/forumdisplay.php?f=100)
-   -   Stamper RV-10 accident Preliminary Report (https://vansairforce.net/community/showthread.php?t=143587)

pvalovich 11-10-2016 12:37 PM

Stamper RV-10 accident Preliminary Report
 
Door came open. Check out this prelim report:

http://www.ntsb.gov/_layouts/ntsb.av...05X23019&key=1

Have you RV-10 folks - and others with pop-up canopies - really developed a detailed step-by-step checklist for what you're going to do if something comes open?

airguy 11-10-2016 12:56 PM

Man, I really hate to see that. That's the one reservation I have about building a 10 for my growing family, is the door latch design.

JonJay 11-10-2016 01:01 PM

Very sad. Fly the Airplane!

I recently posted about my flight instructor many years ago who would purposefully open doors, grab the yoke, open a window, close the throttle or mixture,... basically purposefully distract you until you no longer panicked.

It was also noted that in todays training environment, that instructor might have lost his job for this. Too bad. This was an avoidable accident.

Bottom line, Fly the Airplane.

Thanks for posting this as a lesson to us all.

Carl Froehlich 11-10-2016 02:08 PM

Quote:

Originally Posted by airguy (Post 1125743)
Man, I really hate to see that. That's the one reservation I have about building a 10 for my growing family, is the door latch design.

As I have lost an RV-10 door due to a C130 prop blast, I'm sensitive to the issue. This is what I told the guy who bought my RV-10:

N7ZK?s doors have primary and backup locking devices, and the SkyView alarms if all four primary locking pins are not in place. The doors will last a lifetime if you don?t violate the rules:
1. Doors shut and locked before engine start.
2. Assume your passenger did not lock his/her door ? verify before engine start.
3. After engine start verify all four door pins in by observing the Green door indication on the SkyView EMS display.
4. Doors shut and locked anytime the engine is running ? no matter how tempting to do the hot passenger pickup/drop off.
5. If parked anywhere but in a hangar, doors shut and locked unless you are standing next to the door. So for all fueling, moving to park, etc. doors shut and locked. In other words, unless you are getting in or out of the plane, doors shut and locked.

Carl

rv7boy 11-10-2016 02:25 PM

Hey guys, there is already a thread on this here.

I'll defer to a another moderator or Doug himself if these should be merged or one deleted.

1001001 11-10-2016 02:59 PM

Quote:

Originally Posted by rv7boy (Post 1125761)
Hey guys, there is already a thread on this here.

I'll defer to a another moderator or Doug himself if these should be merged or one deleted.

That one is a memorial thread and probably shouldn't be cluttered with details of the incident. IMO

Auburntsts 11-10-2016 04:46 PM

Quote:

Originally Posted by pvalovich (Post 1125738)
Door came open. Check out this prelim report:

http://www.ntsb.gov/_layouts/ntsb.av...05X23019&key=1

Have you RV-10 folks - and others with pop-up canopies - really developed a detailed step-by-step checklist for what you're going to do if something comes open?

Yes-it's only 2 steps:

1. Fly the Plane
2. Land Immediately.

Notice there are no steps about the door itself. I will make no attempts to save the door--period. If I've got pax and they have the wherewithal to do try something then they can, but I will only focus on putting the plane safely on the ground. YMMV....

scsmith 11-10-2016 04:48 PM

I wonder if it is out of the question to think about moving the hinge points of the door to be along the front edge or angled so the door won't suck open? Like a Cirrus. (I admit I'm making an assumption here; I don't know for sure that Cirrus doors don't suck open).

There are plenty of flight-critical things that we as pilots must get right, or cope with the error while continuing to fly the airplane. And yes, I'm usually an advocate of the idea that it is OK to rely on the pilot to be sure to get it right.

But if a fairly uncomplicated engineering solution can save lives, why not?

Are there any reasons why it would be very difficult or impossible to relocate the door hinge points?

rvbuilder2002 11-10-2016 05:29 PM

Quote:

Originally Posted by scsmith (Post 1125791)
I wonder if it is out of the question to think about moving the hinge points of the door to be along the front edge or angled so the door won't suck open? Like a Cirrus. (I admit I'm making an assumption here; I don't know for sure that Cirrus doors don't suck open).

There are plenty of flight-critical things that we as pilots must get right, or cope with the error while continuing to fly the airplane. And yes, I'm usually an advocate of the idea that it is OK to rely on the pilot to be sure to get it right.

But if a fairly uncomplicated engineering solution can save lives, why not?

Are there any reasons why it would be very difficult or impossible to relocate the door hinge points?

Unfortunately Steve,
Even a different opening action of the door doesn't always protect from accidents caused by a pilot allowing him/her self to become distracted.
The NTSB files are full of them.
Here is a high profile one that I am personally familiar with from when I lived in PHX....... https://aviation-safety.net/wikibase/wiki.php?id=37373

And yes I think it would be fairly complicated to move the hinge points. The fwd "A" pillars are considered rollover structure. Not that it couldn't be done, but there are numerous issues that would have to be dealt with.

majuro15 11-10-2016 06:09 PM

So not to make assumptions, but based off the report, could it be that the door was never closed in the first place? I'm wondering if the annunciation system had a fault so he didn't realize it wasn't fully latched?

Either way, it's something we can all learn from wether it was a human or mechanical failure. Very sad that we lost a member of our flying family.

TS Flightlines 11-10-2016 06:12 PM

another thought--
 
NOT wanting to hijack the thread, or go off on a rabbit trail, but learn something from my friend Bruce's passing.
BUT---I am interested in the cause of the fire. I have some obvious concerns here, but quite possibly one glaring detail that most of us dont think about. After the impact, was the fuel system intact, or was the mechanical pump or hoses damaged by the impact? My question my sound crazy, but if the boost pump was running, and the FWF hoses or pump were in fact damaged so fuel could escape, then the boost pump was dumping fuel that could have contributed to the post impact fire. I dont know if any of that is fact, and certainly dont want to speculate.
But, is this is the case, we need to address this.

Bruce---we wil miss you my friend, and perhaps we can learn something from this, to prevent is from happening again.

Tom

JonJay 11-10-2016 06:52 PM

Very sorry for your friend and the loss in general.

dave4754 11-10-2016 06:55 PM

So Very sad
 
It is good to know these things and try to imagine ourselves in this predicament and i visualize myself ignoring the blast of air, the anguish over loosing the door and other things that would surely fill my mind.

This helps to prepare and prepare some more for those unexpected things that will happen up there.

So very sorry to loose a fellow pilot and will do some more inner visuals as a result of these events. Hopefully when the day comes it will help.

mturnerb 11-10-2016 07:30 PM

Quote:

Originally Posted by TS Flightlines (Post 1125810)
NOT wanting to hijack the thread, or go off on a rabbit trail, but learn something from my friend Bruce's passing.
BUT---I am interested in the cause of the fire. I have some obvious concerns here, but quite possibly one glaring detail that most of us dont think about. After the impact, was the fuel system intact, or was the mechanical pump or hoses damaged by the impact? My question my sound crazy, but if the boost pump was running, and the FWF hoses or pump were in fact damaged so fuel could escape, then the boost pump was dumping fuel that could have contributed to the post impact fire. I dont know if any of that is fact, and certainly dont want to speculate.
But, is this is the case, we need to address this.

Bruce---we wil miss you my friend, and perhaps we can learn something from this, to prevent is from happening again.

Tom

I'm guessing impact forces were enough to cause damage to the fuel tanks, so the fuel source is there and so are plenty of ignition sources (exhaust for starters). No aircraft is designed to withstand the very high g loads and irregular application of forces in a high-speed impact resulting from a stall.

I've had a door pop open just after takeoff (not in an RV) and it was very hard to resist the temptation to focus on the door. I was able to climb to pattern altitude and close it, but retrospectively it would have been much smarter to land and deal with it. I was a student pilot at the time and lucky. Agree with the need for ongoing training for unexpected events in critical phases of flight.

Kyle Boatright 11-10-2016 07:54 PM

Quote:

Originally Posted by scsmith (Post 1125791)

Are there any reasons why it would be very difficult or impossible to relocate the door hinge points?

I had a Piper Tomahawk which had doors which resembled the RV-10 doors. Each door had two external hinges along the front edge plus a latch at the top of the cabin that captured both doors and a latch along the lower aft edge of each door. I could envision a similar system on the RV-10, but finding appropriate locations for hinges is the challenge.
,
On the RV-10, the doors are large, with the potential to impart a big twisting moment, so I think you'd want widely spaced hinges.

There is one likely hard point at the bottom front corner of the door where you could tie a hinge into a longeron, but there is no obvious point for a second hinge without structural changes. Glassing a hinge to the A-pillar *might* work, but I don't know enough about glass structures to envision that solution.

If you'd like pictures and/or measurements of the doors and structure around the doors, send me a PM with your e-mail.

pierre smith 11-11-2016 05:17 AM

Nope
 
I've had my -10 for 7 years now, without any backup latches of any kind...not even Van's. If you carefully check the doors for security and both pins inserted, the doors will not open.

Best,

sblack 11-11-2016 05:52 AM

Does anyone know if there are any controllability issues with the 10 with a door open? I would not expect there to be, but aerodynamics are often unpredictable.

Jesse 11-11-2016 06:07 AM

Quote:

Originally Posted by pierre smith (Post 1125855)
I've had my -10 for 7 years now, without any backup latches of any kind...not even Van's. If you carefully check the doors for security and both pins inserted, the doors will not open.

Best,

Both pins inserted and the handle roll pin in the slot. That last part is the critical part that so many fail to mention. I have had 2 doors come open due to this last step being missed (only one by me).

dmaib 11-11-2016 06:27 AM

Quote:

Originally Posted by Carl Froehlich (Post 1125760)
As I have lost an RV-10 door due to a C130 prop blast, I'm sensitive to the issue. This is what I told the guy who bought my RV-10:

N7ZK?s doors have primary and backup locking devices, and the SkyView alarms if all four primary locking pins are not in place. The doors will last a lifetime if you don?t violate the rules:
1. Doors shut and locked before engine start.
2. Assume your passenger did not lock his/her door ? verify before engine start.
3. After engine start verify all four door pins in by observing the Green door indication on the SkyView EMS display.
4. Doors shut and locked anytime the engine is running ? no matter how tempting to do the hot passenger pickup/drop off.
5. If parked anywhere but in a hangar, doors shut and locked unless you are standing next to the door. So for all fueling, moving to park, etc. doors shut and locked. In other words, unless you are getting in or out of the plane, doors shut and locked.

Carl

Rules to live by. Don't get complacent about any of the steps.

William 11-11-2016 06:34 AM

Quote:

Originally Posted by Jesse (Post 1125865)
Both pins inserted and the handle roll pin in the slot. That last part is the critical part that so many fail to mention. I have had 2 doors come open due to this last step being missed (only one by me).

Hi Jesse how was each situation dealt with?

I'm a possible future rv10 owner and It seems if the door swings open during flight that it is highly likely to depart the aircraft, and if that door were to hit the tail surfaces, well..... I know it doesn't look like that happen in Mr Stampers case but knowing if the door opens and will likely depart in flight the appeal to try and close it is a valid one. Perhaps the best form of action during a open door in flight with no runway left would be climb at VX until 2000ft and then attempt to close the door. Thoughts?

TFeeney 11-11-2016 07:28 AM

While this event is horrible reminder to us all to keep flying the airplane, this problem is not unique to the -10. Cirrus has had numerous accidents after the door popped open in flight.

Even in my early training in a Cessna 152 the door popped open during take off (50 ft off ground). At the time, I'll admit that I did the exact same thing as Stamper. I was lucky and it scared me enough to change my reactions in the future.

We can engineer the airplane into a tank that eliminates all risk mechanically, or we can understand the risks and what behaviors we would implement under emergency situations. Even with the best latch, and extensive checklist procedures - we all need to be prepared for the what if.

RV6_flyer 11-11-2016 07:40 AM

Quote:

Originally Posted by sblack (Post 1125862)
Does anyone know if there are any controllability issues with the 10 with a door open? I would not expect there to be, but aerodynamics are often unpredictable.

Years ago, one of my friends not long out of Phase I, had the door of his RV-10 open (and depart the airplane) just after liftoff. He flew the airplane around the traffic pattern and landed. He was one of the first RV-10s to fly in the state of California.

sblack 11-11-2016 09:04 AM

Quote:

Originally Posted by RV6_flyer (Post 1125892)
Years ago, one of my friends not long out of Phase I, had the door of his RV-10 open (and depart the airplane) just after liftoff. He flew the airplane around the traffic pattern and landed. He was one of the first RV-10s to fly in the state of California.

and other than the noise (and the activation of the self butt kicking machine)no issues flying the airplane?

rvbuilder2002 11-11-2016 09:10 AM

Quote:

Originally Posted by sblack (Post 1125904)
and other than the noise (and the activation of the self butt kicking machine)no issues flying the airplane?

I am aware of an RV-10 that lost the passenger door right after take-off, where for reasons unknown, the pilot chose to continue to his home base airport (200 miles away) rather than land back at the point of departure..... :o


So I would guess that a missing door does not cause any controlability problems.

Bill Boyd 11-11-2016 09:42 AM

Would it be impolitic
 
to ask how many doors have departed or tried to depart RV-10 airframes? Starting to sound like a sobering percentage of the fleet has been involved at one time or another. Rest assured I am absorbing all appropriate lessons from this experience for a few years down the road.

Gary 40274 11-11-2016 10:25 AM

Fearmongering
 
While a few doors have departed the aircraft I cannot think of any instances where a properly latched door has opened in flight.

Also considering the number of 10s flying it is a very low percentage.

If a pilot did not latch the door and ignored the warning lights and a door departs it should never cause a crash. We have met the enemy and they are us

Gary Specketer

sblack 11-11-2016 10:31 AM

My jodel has the same kind of door. I look at the latches just before advancing the throttle on each flight - I was taught to double check the stuff that will kill you and on that airplane that really is the only thing - the fuel valve has only 1 position so you won't make it to the runway if it is off and there is no primer to lock. But if I screw up one day because someone is talking to me or there is lots of ground traffic etc it will pop open and depart the plane almost certainly - the air is accelerating over the cockpit generating lots of lift. That is a risk I understand and I take it. Everyone has their own threshold of acceptable risk. I plan to do the same on the RV4 - develop a habit/procedure and stick to it. Not 100% foolproof but what is? Others might decide having a safety light is necessary and I totally get that.

I found a youtube video last night of some LSA type airplane in the UK landing after the canopy popped open. It was a tip-up. The guy hit the crops just short of the runway (like 5 ft) and the airplane landed on its nose, NG collapsed, prop hit the grass and it slid along the grass for 50 ft. I suspect he had increased drag and lots of distraction and messed up the landing. The video was from a go-pro of an airplane holding short to takeoff and you could hear the guys cringing as they watched the thing drag its nose down the grass runway. No injuries. So these types of things are not that rare. It comes down to being able to fly and manage the issue at the same time, which evidently is not easy.

flion 11-11-2016 10:35 AM

Quote:

Originally Posted by scsmith (Post 1125791)
I wonder if it is out of the question to think about moving the hinge points of the door to be along the front edge or angled so the door won't suck open? Like a Cirrus. (I admit I'm making an assumption here; I don't know for sure that Cirrus doors don't suck open).

The door will still suck open, just not all the way. I've flown a C-172 with an open door and also a Duchess. Virtually impossible to close and latch without slowing dangerously down, so it's better to just land as quickly as possible and close the door. The test pilot for my RV-6A had the canopy come open on him on the second flight and was unable to close it; others have reported the same. I have to admit, a fully open door on my RV-10 would be more distressing but I'd rather lose the door than the plane. And some planes (think jump planes, for instance) get flown with the door removed and operate safely. That door, while important, is not critical to a safe conclusion of flying. And these incidents happen in all types of aircraft; it's not an RV-10 issue as far as I can see (a per capita breakdown would be needed for an accurate assessment here).

I'd like to add a line item to Todd's checklist: slow the aircraft to approach speed. It might make the difference between losing/not losing the door. And apart from not wanting to lose the door itself, I really don't want to risk it flying back and hitting the tail. But don't slow down so much you get yourself into other kinds of trouble.

Jesse 11-11-2016 07:29 PM

Quote:

Originally Posted by Gary 40274 (Post 1125928)
While a few doors have departed the aircraft I cannot think of any instances where a properly latched door has opened in flight.

Also considering the number of 10s flying it is a very low percentage.

If a pilot did not latch the door and ignored the warning lights and a door departs it should never cause a crash. We have met the enemy and they are us

Gary Specketer

Both of these pins were inserted. The problem is that the roll pin was not fully or at all in the slot. If your button is not popped out, your roll pin is not in the slot, and your door can come open in flight. I know this for a fact. Doors don't just depart because the rear pin isn't in the hole. The Cam didn't keep this door from coming off. The forces on the door caused the handle to rotate, withdrawing the pins and rotating the Cam. A strap is the ONLY way I know of to be sure that your door won't depart the aircraft. The products on the market will help in getting the door closed, but hey will not prevent it from departing the aircraft or even from coming open, as proven here.

rightrudder 11-11-2016 08:52 PM

Quote:

Originally Posted by flion (Post 1125932)

I'd like to add a line item to Todd's checklist: slow the aircraft to approach speed. It might make the difference between losing/not losing the door. And apart from not wanting to lose the door itself, I really don't want to risk it flying back and hitting the tail. But don't slow down so much you get yourself into other kinds of trouble.

Good point. If you did lose the door and it hit the empennage on the way back, it would do a lot less damage at this lower speed.

Condolences to friends and family of the pilot.

ScottSchmidt 11-11-2016 09:05 PM

Quote:

Originally Posted by Carl Froehlich (Post 1125760)
As I have lost an RV-10 door due to a C130 prop blast, I'm sensitive to the issue. This is what I told the guy who bought my RV-10:

N7ZK’s doors have primary and backup locking devices, and the SkyView alarms if all four primary locking pins are not in place. The doors will last a lifetime if you don’t violate the rules:
1. Doors shut and locked before engine start.
2. Assume your passenger did not lock his/her door – verify before engine start.
3. After engine start verify all four door pins in by observing the Green door indication on the SkyView EMS display.
4. Doors shut and locked anytime the engine is running – no matter how tempting to do the hot passenger pickup/drop off.
5. If parked anywhere but in a hangar, doors shut and locked unless you are standing next to the door. So for all fueling, moving to park, etc. doors shut and locked. In other words, unless you are getting in or out of the plane, doors shut and locked.

Carl

That is a good list for the door Carl. I follow the same rules. My first "almost lost the door" moment was an Apache or Blackhawk taxiing by my plane at Conroe just after I opened the door and got out. I never walk away without doors closed, chalked and rudder lock in.

This is such a sad and avoidable accident. In Phase 1 there are so many things to think about and new procedures to process. It is easy to see how things get overlooked.

-Make sure door lights/sensors are installed on your planes. Maybe we need a screaming buzzer that goes off if doors are open and engine is above 1800 RPM.
-Have your checklist with you at all times. I have never taken off without going through my list. I always close the doors and check.
-Practice, practice, practice. What if...engine quits, bird strike, door comes off, window blows out, electrical fire/failure, tire blows, passenger throws up, alternator fails......
-Before first flight, pay the money for RV-10 transition training even if you have RV time. I flew with Mike Seager for 4 hours and learned so much I went back a second time before my first flight. I did my first flight knowing with a high level of confidence I could land the plane on a 4000 ft runway from pattern altitude with no power.

Phase 1 is scary and dangerous without proper training, practice, thoughtful procedures and help from experienced people. It should be almost routine with them but should still be scary to keep us ready if something goes wrong, but should never be dangerous.

I am always available to help if you have any concerns as many of us on this forum are. Please call (801-718-1277) or come fly with me in my plane if you have any reason to think you need some help. I am not a CFI, or an expert test pilot but I have 1250 hours in the RV-10 and have learned a lot along the way. Still learning every day......The best thing to do is to fly with a transition trainer like Alex and Mike (I am sure there are others), they will increase your skill at the fastest rate.

The goal is 0 fatalities.

pierre smith 11-12-2016 08:40 AM

5
 
IIRC correctly, this makes number 5 to lose a door.

Best,

Kyle Boatright 11-12-2016 08:45 AM

Quote:

Originally Posted by pierre smith (Post 1126123)
IIRC correctly, this makes number 5 to lose a door.

Best,

With 814 RV-10's flying, that's about .6% of the fleet. I'd bet there have been at least as many unreported losses (I'm aware of one locally). Plus all of the near-misses, reported or unreported.

BobTurner 11-12-2016 08:56 AM

Quote:

Originally Posted by pierre smith (Post 1126123)
IIRC correctly, this makes number 5 to lose a door.

Best,

Does that number include the pilot who deliberately opened the door in flight, to clear smoke in the cockpit (and then executed a safe off-airport landing)?

togaflyer 11-12-2016 01:25 PM

Bruce was my friend and just a really great man. But from this tragic incident, we need to look at how we can enhance our safety of flying by developing actions and skill sets to address emergencies. From an open door to loss of engine power. You cannot wait until "it happens" before you have a plan. What would you do, whats your procedures. An emergency check list is necessary, but it is subject to time restraints, a crew vs a single pilot operation, altitude, type of emergency, etc. Put your emergency procedures and "what ifs" to memory. Sit in your airplane every so often and practice every emergency procedure possible until you have it to muscle memory. What would you do with a door. Fly the airplane, Reduce speed, deploy partial flaps, slow flight, side slip away from the open door, turns away from the open door, direct to airport, declare an emergency. What ever you decide for procedures, practice them.
Such a sad and preventable loss of life.

Jesse 11-12-2016 02:42 PM

Quote:

Originally Posted by pierre smith (Post 1126123)
IIRC correctly, this makes number 5 to lose a door.

Best,

I think it's a WHOLE LOT more than that. I'd estimate at least 30-50.

rvbuilder2002 11-12-2016 04:09 PM

Well, my estimate would be 15 - 20.

Avi8tor857 11-17-2016 09:10 AM

First I would like to say I'm sadden by the lost of anyone perusing our shared passion of aviation, He seems to have given so much to his community.

I've monitored these boards for a long time so forgive an outsider butting in.

I'm not going to second guess what happened and decisions made. I understand why everyone is saying that you can't design an airplane where nothing could go wrong, so as pilots we must practice and make it second nature to fly the plane first and foremost. I'm right at 100hrs of PIC and even in that short time I've had a flat tire, luckily while taxing, seems the mechanic pinched the tube when putting it on. I've had the window pop open on the 172 during take off. I actually said to myself out loud ignore the window and fly the plane more than once until I was at a safe altitude to deal with it. However a 172's window can be opened below a certain speed with no damage, so I kept the plane below that speed but well above where I would be concerned about stalling at the angle I was climbing out at.

Though I'm a low time pilot, I do have a strong engineering background.

The door design on the RV-10 is my hesitation on ordering the kit, I've bought all the tools and set up my shop. Sure one would expect damage and or separation if you open it at 160kts on a gullwing door. However at Vx or Vy or any other reasonable speed during take off and climb out the door shouldn't separate by any Engineering standard I can think of.

We owe it to people on the ground we fly over if not ourselves to think long and hard; is the door design acceptable. Part of the reason someone would try to close it in a critical stage of flight is knowing the door will separate and could hit the plane or someone on the ground. As builders we are the ones responsible if someone files a lawsuit, so if you sell your plane how confident are you on that door?

Trying to design warning systems and adding extra latches is approaching the the problem from the wrong direction. You don't fix an safety problem by making it more complicated you fix it by making it simpler. The simplest solution would be one that made the door opening below maneuvering speed an non-event.

IMHO, Either the door needs to be designed like the cirrus hinged in the front so that if the door latch is released the door opens slightly but isn't pulled fully open and stays in the the boundary layer so that you have a higher speed in which the door would be damaged. Or the hinges and mounting points need to be beefed up so that there is a reasonable maximum speed in which the door could be opened and not damaged. One other thought is to keep the hinges at the top but change it so the hinge line runs about 45 degrees from where it is now so that at least 50% of the force applied to the door would be in the normal mode of the hinges and a closing force. The only other rework that I can think of is possibly split the door at about the line where the aluminum/fiberglass meet. and have a bottom door and a top door, so that there is less material in the fiberglass part to cause drag and rip off... though again this is a more complicated operation and goes against my adage of making it simpler.


Now from the latch design itself, it is very similar to the latch on the T-Top of the third generation F-Body (1989 Firebird as an example). The F-Body had a hard plastic guide in which steel pins are extended into. In the late 80s GM decided to change the heavy glass out for Lexan. These were latter recalled due to crazing but there was another issue they flexed. I know a few people that didn't opt to trade them in for the Glass version and out of those I know two people that have had one fly off. Now with the T-top latch you can lock it (with the key) closed which rules out the handle getting opened accidentally or by some mechanical cause. Also there is no way you can close the latch without the pins engaging the body. Of the two that I know flew off one was locked, the pins were extended, and the guides were in good shape. Why am I bring up what most consider a bad car anyways? Because due to some level of body flex, pin length and the more flexible lexan panel even a properly secured and locked T-Top can come loose using the same basic design at highway speeds.

Please forgive the newbie posting a very long post.

Jesse 11-17-2016 09:21 AM

Quote:

Originally Posted by Avi8tor857 (Post 1127459)
The door design on the RV-10 is my hesitation on ordering the kit, I've bought all the tools and set up my shop. Sure one would expect damage and or separation if you open it at 160kts on a gullwing door. However at Vx or Vy or any other reasonable speed during take off and climb out the door shouldn't separate by any Engineering standard I can think of.

THe part you are missing is that in cruise, the relative wind is much different than at initial climb. At a high angle of attack, with the relative wind, the door is acting as a sail and is MUCH MORE likely to depart than at a much higher speed in level cruise. Perhaps better stated, it will depart much more quickly at the high angle of attack. I know this from personal experience, all engineering calculations aside.

vic syracuse 11-17-2016 10:07 AM

Quote:

Originally Posted by Avi8tor857 (Post 1127459)
First I would like to say I'm sadden by the lost of anyone perusing our shared passion of aviation, He seems to have given so much to his community.

I've monitored these boards for a long time so forgive an outsider butting in.

I'm not going to second guess what happened and decisions made. I understand why everyone is saying that you can't design an airplane where nothing could go wrong, so as pilots we must practice and make it second nature to fly the plane first and foremost. I'm right at 100hrs of PIC and even in that short time I've had a flat tire, luckily while taxing, seems the mechanic pinched the tube when putting it on. I've had the window pop open on the 172 during take off. I actually said to myself out loud ignore the window and fly the plane more than once until I was at a safe altitude to deal with it. However a 172's window can be opened below a certain speed with no damage, so I kept the plane below that speed but well above where I would be concerned about stalling at the angle I was climbing out at.

Though I'm a low time pilot, I do have a strong engineering background.

The door design on the RV-10 is my hesitation on ordering the kit, I've bought all the tools and set up my shop. Sure one would expect damage and or separation if you open it at 160kts on a gullwing door. However at Vx or Vy or any other reasonable speed during take off and climb out the door shouldn't separate by any Engineering standard I can think of.

We owe it to people on the ground we fly over if not ourselves to think long and hard; is the door design acceptable. Part of the reason someone would try to close it in a critical stage of flight is knowing the door will separate and could hit the plane or someone on the ground. As builders we are the ones responsible if someone files a lawsuit, so if you sell your plane how confident are you on that door?

Trying to design warning systems and adding extra latches is approaching the the problem from the wrong direction. You don't fix an safety problem by making it more complicated you fix it by making it simpler. The simplest solution would be one that made the door opening below maneuvering speed an non-event.

IMHO, Either the door needs to be designed like the cirrus hinged in the front so that if the door latch is released the door opens slightly but isn't pulled fully open and stays in the the boundary layer so that you have a higher speed in which the door would be damaged. Or the hinges and mounting points need to be beefed up so that there is a reasonable maximum speed in which the door could be opened and not damaged. One other thought is to keep the hinges at the top but change it so the hinge line runs about 45 degrees from where it is now so that at least 50% of the force applied to the door would be in the normal mode of the hinges and a closing force. The only other rework that I can think of is possibly split the door at about the line where the aluminum/fiberglass meet. and have a bottom door and a top door, so that there is less material in the fiberglass part to cause drag and rip off... though again this is a more complicated operation and goes against my adage of making it simpler.


Now from the latch design itself, it is very similar to the latch on the T-Top of the third generation F-Body (1989 Firebird as an example). The F-Body had a hard plastic guide in which steel pins are extended into. In the late 80s GM decided to change the heavy glass out for Lexan. These were latter recalled due to crazing but there was another issue they flexed. I know a few people that didn't opt to trade them in for the Glass version and out of those I know two people that have had one fly off. Now with the T-top latch you can lock it (with the key) closed which rules out the handle getting opened accidentally or by some mechanical cause. Also there is no way you can close the latch without the pins engaging the body. Of the two that I know flew off one was locked, the pins were extended, and the guides were in good shape. Why am I bring up what most consider a bad car anyways? Because due to some level of body flex, pin length and the more flexible lexan panel even a properly secured and locked T-Top can come loose using the same basic design at highway speeds.

Please forgive the newbie posting a very long post.


Really? Redesign??? I don't mean to sound cold here, as I knew Bruce and feel terrible for him and his family, so my comments are no reflection on Bruce. Please read that part again.

The RV-10 fleet is quite large now, and the track record is there that IF you close the doors properly they stay attached. I personally have over 2000 hours of RV-10 time, and others may have many more. We ALWAYS call "doors closed and locked" prior to entering the runway. I even have the door light system installed with an interlock on the throttle so I don't get used to 2 glowing red lights when the doors are open in the summer.

If you forget to close the doors, they will come open. Probably at the worst time. If you forget to put fuel in the tanks, the engine will quit. We could go on and on about the impact of forgetting to do things prior to takeoff. Use a checklist, and go over it twice during the testing phase. It is a new airplane, habits aren't built yet, and each airplane is different and will have it's own nuances. Part of Phase I is to build a checklist appropriate to your aircraft, in the order that makes sense.

Vic


All times are GMT -6. The time now is 08:11 AM.