Past Gyro Accident

[mceagle]

Chuck Irby's accident. It is not with any pleasure that I bring this topic up again but I read back through the relevant thread and I could not find any findings as to the cause of this unfortunate accident. I recall at least a couple of similar accidents in Oz, and as much as we do not like to speak ill of the deceased, both accidents caused a change of thinking in Oz and a lot was learn't that possibly contributed to no repeats of the same thing.
I only knew Chuck through the forum and I would suggest that he would have been saddened if he knew his passing was in vain. I am sure that he would have wished that the cause be made public and perhaps save another life, (if not more).
Many Gyronauts are offended by others suggesting that they modify certain unsafe practices but I have found that if enough people bring it to their attention often enough, they will eventually come around.
I could list many such practices that have been learnt the hard way and perhaps that would not be a bad idea - a list of unsafe practices and the reasons why they are unsafe. I am sure many Instructors and technical members could contribute to this.

[birdy]

I agree Tim.
It happened to Chuck Irby,so it could happen to any of us.
Complacency would be one of the bigger causes,not that I'm sugesting it was the cause in Chuck's case,but I know a bloke round ere,a non pilot,that we now call chop chop.He simply got too close to an ideling machine,and needed 38 stitches in his arm as a result.He's damn lucky he didnt get draged in coz it was on the down side of the prop disc.

Electric starts and park breaks would also help.

[donshoebridge]

There was a show on UltraFlight Radio (online) just this past week where the topic was Decision Making, which current accounts for more than 70% of all aviation accidents. I think there is something to be said concerning Decision Making, and like a good pre-flight inspection, good Decision Making should be as automatic as reaching for a check list.

You're right Tim. A detailed list of do's and don'ts would be a huge benefit to us all. I'd even go as far as to have it printed in magazines, and maybe go as far as to have the PRA include it in a package with every new member they get.

[Victor Duarte]

Tim , it would be very helpfull, particularly for newbies like me.
Thank you

[Doug Riley]

I met Chuck Irby last year at B-days. He was a very likeable fellow.
He was also very interested in gyro safety.

I'm as guilty as the next guy of sometimes being casual around pull-start Rotaxes. Part of the reason we get sloppy is that these engines are very much safer than the hand-propped VW's and Mac's we started with.

In a throttle operated by a pull-cable, you rely on an unseen spring to return the carb slide to its idle position. One way to make sure the slide hasn't stuck (with the cable going slack) is the close the throttle smartly and listen for the slide hitting its idle stop, just before you pull the starter. If there's no click, you better investigate. Also, if you move the throttle control to idle and then feel less resistance than usual when you advance the control again, the slide is likely stuck.

Also (and again, I'm guilty here), don't position the start handle in a place that requires you to stand beside the engine and pull parallel to the wheel axles. This position puts you close to the prop (less time to get out of the way if it surges) and, at the same time, takes you away from the throttle and mag switches that you could use to stop a runaway engine.

Get a longer rope and route the rope forward with one or more pulleys. Position it so that you can stand next to the seat and pull forward, not to the side. If you're a real gorilla, you may be able to pull it while stitting in the seat -- but I've never been able to give a very hearty yank from that position. In either case, a favorite position for the rope is up and over a pulley mounted on the rotor head cheek plates. It's a good idea to secure the handle with a strip of velcro when it's not in use, and to run the rope through a piece of plastic hose. This makes it less likely that a broken rope will find its way into the prop or rotor (yes, it has happened).

If you can rig up a parking brake and/or electric starting, do so. Both add a safety reserve to your start procedure.

[Udi]

Doug - you are not going to the gym often enough if you can't pull start from the seat... You've got to strengthen those pull muscles ;)

This kind of accident may be caused due to human factors and/or mechanical failures. The best pilots are not immune to either cause. This is why we have to minimize the consequences, if it were to happen to us.

I was witness to an incident similar to Chuck's in which the pilot walked away (for a fresh pair of underwear). This pilot started his AAI-modified RAF with the throttle close to full open. He was sitting in the seat, unbuckled. When the engine started he had about 3 seconds to react before colliding with a wall at high speed. Luckily, he did (and I had to get my heart going again). The only reason he walked away was because he was sitting inside the cabin and not standing on the side.

If you want to be really safe, use an electric starter or pull-start from the seat. Pulling while standing in front of the landing gear is safer than standing by the engine - no question - but I don't think this is very safe when your engine has more than 40-50 HP. A powerful engine would run you over at full power, even if you were standing ahead of the landing gear.

Udi

[rehler]

I was told that the throttle on Chuck's gyro got pushed to the full position by someone else (unknown person, while the gyro was sitting on display). Chuck did not know that it had been changed from the idle position. The throttle was on the left side of the gyro and Chuck was standing on the right side of the gyro when he started it. It then quickly jumped forward tripping him into the prop.

[Doug Riley]

Always, ALWAYS check the throttle position by physically cycling it up and back before you fire up. Listen for the carb slide or butterfly contacting its own stop. I also give the handle a last tap against its stop with the flat of my hand just before pulling the rope or hitting the starter. Know what you'll do if it surges. Be able to reach the kill switch without looking or hesitating. If possible, have your finger right on the kill switch as you pull a manual starter through.

As for going to a gym, Udi, I visited Jim just last week, only he don't spell his name that funny foreign way.

[birdy]

Udi,you don't need a gym to strengthen those PULL muscles. :p :D

[Udi]

Well, Birdy, I really don't need it :cool: but I didn't want to offend anyone... :rolleyes:

Udi

[KenSandyEggo]

I go to the gym almost every day. I drive right past it on my way to Baskin-Robbins.

[Friendly]

Tim , we had another gyro accident a few months before Chucks. It was told to me that Chuck was asking what could be done to possibly prevent this from happing to someone else. I believe he mention something about a boat kill switch which would pull out if the craft moved too far from the person operating it. I have thought about a kill switch on the mast for my Bensen but I will probably adopt a starter to the Mac. I started my Mac up the other day after installing Ricks CDI. I chained it to a tree and held the mast back by hand then I throtted it up. I have a lot more respect for it now than before. I also had a friend who is 230 lbs and benches 400. The machine still crept forward and was held by the chain. I will do something. Starter, kill switch, something. We all miss Chuck.

[GyroRon]

Well, Birdy, I really don't need it :cool: but I didn't want to offend anyone... :rolleyes:

Udi

With all the kids you got I know you don't need that kind of exercise!

[mceagle]

It looks as though the Instructors have more work to do. It is indeed a bad mistake to start any aircraft engine without first checking throttle position. Such accidents are still happening and will keep happening as long as the pilot is not taught correctly or has become complacent.
Many offer the common excuse that "you can lead a horse to water but you can't make him drink". This is a cop out! - Of course you can make him drink, at least in 99% of cases anyway. The Instructor has control over the issue of his licence, and also has a respected rank over the student or newchum.
Why not introduce them to one or more of the following:-
a friend who has fingers or a hand missing,
another who has been cracked on the head with a rotor,
perhaps another who has to watch because he cannot afford a rebuild,
there is always the one in hiding pending a house threatening liability claim,
if that does not pull them into gear, then introduce them to a fello gyronaut's widow and family.
I think we all know someone who fits one or more of the above descriptions. The worst thing is that is also possible for an innocent party to be injured or killed.
Sounds drastic but what price to save a human life.

Doug has described well how easy it is to check Rotax throttle positions, but this is only the tip of the iceburg, made up of the many ways and means that gyronauts can utilize to try to kill themselves.

[Paul_Zurawski]

I have seen quite a few gyro pilots hand prop their engines without one very important piece of safety equipement....wheel chocks. I have never started my gyro without wheel chocks in front of each main tire...and I dont mean those little chocks...I have the large rubber ones that will chock a tractor trailer.

[EI-GYRO]

Hi Guys, (and MJ)

I use a chicken switch on the mast, about head height.
When I pull through the VW to prime it, the ignition is off,
and I push the spring switch on the mast for the pull to start
the engine. If all is OK when it starts, I reach down and switch on the
ignition switch. If I dont like something, I just step back, and it stops.

I also have a strobe mounted at eye level on the mast, which is
damn all use as a strobe, but very good at warning me if I should leave
the ignition on by mistake. This can happen if the engine cuts out at idle.

Engine surges on startup are very common, for all sorts of reasons.
Mostly folks just get a brief fright, but sometimes......

We have had three startup runaways in Ireland last year, that I know of.

Cheers

Fergus.

[donshoebridge]

Wheel chocks... Chicken switch... Strobe light... Except for the strobe, these can easily be implemented on a 2-stroke machine.

Anyone know if "runaway" accidents/incidents are tracked on the NASA or FAA database?

[Alan Coats]

I did a Google search on "kill switches" once, and found a lot of them listed for use in drag racing motorbikes and ATVs. They use a tether, similar to the ones on wet bikes, to kill the engine if the rider is thrown off. The tether uses a cable instead of plastic.

Seems like these could have a use as a safety cut-off switch on gyros.

Alan

Alan

[Doug Riley]

Well, maybe not. The prop isn't going to stop instantly... but the machine will travel forward to where the pilot is standing in a flash.

The real lesson in all of this may be that an aircraft can't be reduced to a consumer product like a Jet-Ski can. You just have to be more professional around these inherently dangerous flying gadgets.

I did a little article for the PRA mag on the topic of starting procedures and Emailed it to the office this morning.

[Udi]

With regard to using electrical switches as protection for a runaway/runover gyro, I would like to remind everyone that electrical switches have two main modes of failure:

1. The switch may not work when you need it to work. In this case, a mast mounted switch, for example, may get stuck closed and not open the circuit when you let go. Remember that you trust your life with a simple mechanical device.

2. The switch may work when you don't want it to work. In this case, an emergency kill switch may kill the engine while you are in the air, causing an unintended emergency landing or worse.

So, when you are installing an additional control on your gyro, like an additional kill switch, you are making the system more complicated, thus more prone to failures. This is ok, as long as you have considered everything that can go wrong with this new device, and remembering what a failure of this device can mean to you and your gyro. Keep doing this mental exercise for every part in your gyro and you will have long life.

Udi

[Doug Riley]

...and prosper...

[Alan Coats]

Doug said -
"I did a little article for the PRA mag on the topic of starting procedures and Emailed it to the office this morning."


That's great! I'll look forward to seeing it. I am sure that I will learn all this in my training, but it is good to read about these things ahead of time. Might even make a difference on how I build something on my machine.

Thanks,
Alan

[Dean_Dolph]

........I did a little article for the PRA mag on the topic of starting procedures and Emailed it to the office this morning.Good to see you contribute to the mag! Please don't stop with this one.

I would suggest to everyone that sending articles straight to editor Rick Gilley might be more efficient. Chuck B. posted Rick's email address in the 'Magazine Article Topic' thread http://www.rotaryforum.com/forum/showthread.php?postid=47208#poststop

[LARRYEBOYER]

I hate to admit this one almost fatal error. I am a big, big believer in Murphy's law. I was demonstrating my e-81 rebuild for a friend who was a builder for years. I had the throttle closed and was attempting a hand prop. He was at the front of the gyro. I made the ignition hot and pulled the prop through. It started in open throttle. I had my foot on the landing gear bracing the craft. If it wasn't for my friend being around the front of the aircraft , (I think a lesser experienced person would have paniced and ran) He put his body into the front nose of the pod and held on. I was able to reach the switch and shut it down.I was amazed to find that a bracket I had constructed for the throttle cable had shifted and opened the throttle even though I had the throttle closed. I never caught it. I had started the engine many times without any assistance. I was so lucky Mr. Miller was there or I could have been prop fodder/hamburg.I now always check the carb and throttle every time to make sure it is closed. Good advice from all. Mr Murphy is alive and well!!!

[bones]

This is just something that i TRY to do most times when starting mine as most time i'm the only one there, it's very simple just wheel it around and put the front tyre against my trailer or the shed door, that way if something should go wrong i has a couple of seconds before its the **** is all gonna hit the fan, then when i'm ready just spin it around get in and go.

[donshoebridge]

Being that most gyro's are open for inspection, checking for proper throttle operation (ie, the cable, the carb, etc.) should be part of the pre-flight.

I'm not trying to slam you Larry. It's just that throttle function is not one of the more common areas that gets checked. I'm sure we all were/are guilty of this to a degree.

[Cobra Doc]

Don't think for a minute that these accidents are limited to gyros. The hard wing guys make the same mistake on a weekly basis. The first aircraft accident I ever saw was a dead battery in a Super Decathlon. No tie downs, no chocks, no rated pilot in the drivers seat, full throttle. Fortuneatly only the pilots ego and butt were bruised. The Decat was a big mess. I'm not sure it was ever rebuilt after hitting a wall following a 75' run full bore.

[Doug Riley]

At an ultralight flyin a dozen or so years ago, it was about 6:00 a.m. I was still in my tent. Other participants were, too. The tents were in a line alongside one of the runways. We heard a Rotax go to full bore and an aircraft start its takeoff run -- typical wise-guy early bird. Even from inside a tent, you could follow the plane's takeoff and curving flight overhead by the sound of its engine. Then there was a tremendous bang, followed by crackling and a deep thud -- very fatal-sounding noises.

Upon clambering outside, we saw the remains of a brand-new 2-place Kolb dangling vertically out of a tree. But no one was in it.

The battery had run down and the (new) owner had hand-propped the machine from behind. It went to full throttle, tore off down the runway by itself, flew up in a climbing arc while barely clearing the line of tents, and
was stopped from departing the area for Chicago by crashing full tilt into the tree -- followed by falling out of the tree with a thud.

A beautiful plane was demolished. All us tenters narrowly escaped becoming snacks for that prop.

Somebody who gets TOO used to electric starting is often more dangerous when the battery goes dead that someone who hand-starts all the time.

[birdy]

Maybe a good thing you can't hand start a rotax 4 banger then ay??

[Chopper Reid]

or a fuel injected Suby 2.2 !!!

Udi, I'm with you in regard to any extra switches that may or may not work when required.

[scott heger]

For those that might have missed this post in April last year, just a ugly reminder:
Mac+prop=Win, right arm.....lost

--------------------------------------------------------------------------------

Last week a new owner of a Benson/Mac powered gyro nearly lost his arm with a prop strike at our airport.
The owner had recently acquired the gyro and had asked me to test fly it for him. I questioned him about his prior experience , and he told me that he had "some" time in helicopters. Further questions revealed that he was a student in helicopters, had 10-15 hours and had no license. I told him to go get some training in a gyro, and after that, I would be willing to balance it, but not fly it, as it had no insurance, a airport requirment. He was quite insistant on flying it without going and getting any more training,, and after spending 45 minutes telling him all the places and reasons to get training, he was not listening. I finally told him that if he really insisted to do it by himself, go to El Mirage where there wasn't much to run into, and to take a safety companion.
Well apparently, he didn't like everything I told him, and went over to the other side of the airport to talk to (yes its him) Dennis Fetters. I was told Dennis also told him(according to a third party) to seek training, and that the Airport(AJO) was a poor place to practice and learn.
I show up to the airport after being gone for two weeks, and 3 people come up to me with "did you here what happened to the other gyro". Well my heart felt heavy, as I felt he had crashed.....but, no. He had hand prop started the Mac alone(witout chocks), and managed, (story varies how) to getting the throttle wound up, and it nearly severed his right arm, leaving skinless hanging flesh, bone and blood everywhere. The gyro continued in a semicircle, puncturing a hanger door and imbedding itself. The picture of his arm injury is so grusome, that I am not going to post it, but you would NEVER hand start another Mac if you saw the damage it did to him. All three paramedic units from the City of Corona responded, along with a Mercy Air helicopter, and transported him to Loma Linda Hospital trama Center. The quick action saved his life, the arm is still in doubt.
I can only wish for his recovery, but his life will be changed forever. To all you newbies, please listen.... get qualified training and instruction. This is a example where the gyro damned near killed the "pilot" and he was no where near getting to a runway yet. Listening to what other experienced people told him, would have saved a immense amount of pain and suffering.

Scott Heger,l Laguna Niguel, Ca SportCopter N86SH

__________________
__________________
You are only as good as your last flight

[Harry_S.]

Such a sad, sad and devastating happening. God, why won't people listen.



.

[PW_Plack]

There's a reason for requiring a rated pilot at the controls. This case in 2002 was said to involve an elderly man who reportedly won a flight as part of some sort of contest or raffle, and went to nearby Scappoose Industrial Airport to get his free ride...

On February 12, 2002, about 1500 Pacific standard time, a Piper PA-24-180, N7004P, registered to and operated by the pilot as a 14 CFR Part 91 personal flight, sustained substantial damage when it collided with a fence and trees at the Scappoose Industrial Airpark, Scappoose, Oregon. Visual meteorological conditions prevailed at the time and no flight plan was filed. The private pilot received minor injuries and the passenger was fatally injured.

During a telephone interview and subsequent written statement, the pilot reported that after fueling, attempts to start the engine with the electric starter were unsuccessful, therefore, he decided to hand prop the engine. The pilot stated that he "pulled the prop through six to seven times" to purge the fuel in the cylinders. After this was completed, he instructed his passenger, seated in the right seat, to turn on the master switch. The pilot then turned the magnetos to the both on position, enriched the mixture, and opened the throttle one-quarter to three-eighths of an inch. The pilot also instructed his passenger on the operation of the "T" handle brake system, which had to be pushed in for the Johnson brake bar to work. The pilot stated that he then "pushed on the cowl to verify the brake was set. It was. I pulled the prop, and the engine instantly started". The pilot then started to walk around the wing when the engine RPM increased to high RPM and the airplane began to move forward. The wing knocked the pilot down and the airplane continued to travel across the ramp toward the runway. The aircraft crossed the runway and a taxiway before colliding with a fence and subsequently trees in a park on the west side of the airport.

The aircraft fuselage came to rest against a tree. Both wings and the left horizontal stabilizer separated from the fuselage.

The pilot stated that he does not know how the brake could have been released, and he reported no mechanical malfunction or failure on the NTSB Pilot/Operator Aircraft Accident Report Form 6120.1/2. No ground tie down ropes or wheel chocks were used.

An automated weather observation at Scappoose reported at 1453, clear skies with 10 miles visibility and wind from 330 degrees at 3 knots.

Witnesses at the fuel pumps, reported to a Scappoose Police Department Officer, that the aircraft was traveling approximately 70 to 80 miles per hour when it collided with the fence and trees.

[mceagle]

Post # 14 - "Such accidents are still happening and will keep happening as long as the pilot is not taught correctly or has become complacent".

AND will happen again and again unless something is done about it. There are plenty of intellegent people out there, we must be able to think of something.
Perhaps we could detail a common speil that any member could (and is obliged to) quote to such irresponsible people - eg.

"If you intend to operate this aircraft in any way or manner, then it WILL injure or kill you unless you receive advise and/or training from a PRA recognised Instructor. Indifference to this rule could make you or your family liable for any damage, or costs incurred in the defence of the good name of the PRA".

[Alan Coats]

Could some of you please post pictures of a setup for pull starting your engine from the seat?

It shouldn't be too hard to figure out, but it seems like there is always someone here with a good idea I never would have thought of for doing even the simplest things.

Thanks,
Alan

[Hognose]

A few years ago, Ron Wanttaja owned a Fly Baby (small fixed-wing homebuilt, designed by the late Pete Bowers) that was non-electric-system. It had once been used for glider towing and had a glider-tow hook attached to it.

Subsequently, the FAA banned glider towing from experimental aircraft (there was no accident or reason to do so, just FAA lawyers flexing their muscles). But Ron or somebody discovered that the tow hook was perfect for one-man (safe!) prop-starting.

1. Position the plane in front of a tiedown.

2. Tie a bowline in the tiedown rope, and snap it onto the glider hook.

3. Roll the plane forward to take up any slack.

4. Prop plane.

5. If you screwed up and it's at full throttle, the tiedown will hold it while you can safely go around the machine to retard the throttle.

6. When you are seated in the cockpit, goggles and helmet on, seat-belted in, and in all respects ready to fly, actuate the red JETTISON TOW knob in the cockpit.

7. Don't overdo it when you tie the bowline, or the guy whose tiedown it is will be furious that he has to grunt and strain to get it undone. Likewise, don't mess up the bowline (easy to do if you are new to the knot) and tie a figure-8 slip knot by mistake, or it may cinch down on your tow hook hard enough that it won't jettison.

8. At your home drome, it may make sense to put in an "extra" tiedown anchor with a length of nylon rope permanently tied in a bowline.

The only reason this would be a bad idea in a gyro is the added weight.

cheers

-=K=-

[Doug Riley]

Arrgh, matey, 'tis a sailor's knot we're ta be usin' now, is it? A bowline is a handy knot for all kinds of rope work.

Bensen gyros came equipped with a regulation sailplane tow hitch on the front end for gyrogliding. Some people used to move it to back end of the keel for use during startup, as Kevin describes.

[ahancock]

Take a look at the Butterfly, www.thebuterflyinfo.com. it has the starter rope attached to the mast so it can be started from the seat.
Alan

[joe6558]

The Butterfly website has moved to:

www.thebutterflyllc.com

[Chris Burgess]

Can someone refresh me on the details of a fatal accident at El Mirage some time ago, envolving a KB-3? If it's in a "Rotorcraft" magazine, just give me the month and year. Thanks in advance.

[Chris Burgess]

Along this topic, do not attempt to hand prop a "Showers of Sparks" ignition with the switch in both. The spark is not retarded and you get ignition before TDC. This pulls the prop out of your hand and wacks the "proper" when the prop bounces off the pre-TDC fire. This usually equals something broken or worse, amputated. Know what you are hand proping and the correct way to do so. In my 33 years with the MAC, I've also learned that when it won't fire, turn the prop through very slowly and, IT WILL.!!!

[Dean_Dolph]

Hey, Chris, glad to see you join us!

Having another instructor available to offer insight has value and besides that; there are times that prospective gyro students inquire about finding an instructor in your area. It might help if you add 'Maryland' to Frederick in your public profile.

[Chris Burgess]

"You asked for it, You got it"

[Rotornut]

Chris it sure is good to see you here posting. Hope to see more of ya.
Sunstate Rotor Club. MJ :)

[Chris Burgess]

Waiting for the season to break here, snow on the ground, open cockpit. These old bones get a little cold below 50. Just got my rotor hub back from RAF. Had the non mandantory winglet and main bolt change-out done. Since it is about 5 times overkill, I think it is plently. Spin em up, keep em out of the ground. Thanks for the Welcome.

[Mayfield]

Chris,

Good to see you posting here. Your input will be welcome.

Will you be visiting PHX soon? It seems every time you've visited that we mean to get together but both of us have been tied up.

I hope that by the time you make it to town that I will have a new project going.

R/S

Jim

[Chris Burgess]

My Phoenix daughter moved to Miami, so PHX may not be the place. Maybe Mentone again? You got busy with the Sparrow and I got busy in the SnoBird. I still want to try that one out. Talked to Steve and we all know he was a "hang em out to dry" sort, in that screaming Parson's. The ADIZ around Washington DC has BlackHawks on patrol, Camp David, F-16's. Airspace is a little tight here. Could use a few SH's. Keep that Phoenix sun off those glass rotors.

[EI-GYRO]

Chris, Was that the Bill Dass accident you were asking about ?
If so, most of the interesting stuff appeared on the conference,
courtesy of Craig Wall.

Cheers

Fergus Kavanagh
Dublin, Ireland.

[Chris Burgess]

Fergus, Thanks, that was it. All the way from Dublin!! Imagine that.

[EI-GYRO]

Hi Chris, I remember this accident particularly because it puzzled a lot of folks, and
worried me as I was just considering building a Bensen at the time.

The pilot was performing a very quick pedal turn at slow speed and high power.
There was a bang and that was it. Fell out of the sky.

Initially was felt to be a blade or blade root failure, but still puzzling.

Craig Wall pointed out that with full power and nose high in slow flight, the rotor
would be tilted back about 30 degrees. A full deflection pedal turn would rotate the
machine through 180 degrees in less than a second, requiring the rotor disc to
re-orient itself through 60 degrees in that time. Too much too quick. Violent mast
bumping and snapped a blade off. That is as I remember/understand it.

Reference was made to Bill Ortmeyer and an article he wrote describing this maneouvre. Craig reckoned this might be ok on a slower reaction two-seat machine
but fatal on a single-seater.

Hope this helps.

Fergus.

We are self-training over here (a bunch of us.) so I read the accident reports real
careful. I have 45 hours of crowhops, that's how careful I am.
Saw you on Dan Leslie's video ' How to fly gyros'.

Cheers.

[Chris Burgess]

My only comment, this maneuver is not in the Practical Test Standards for a Private Gyroplane Rating. It meets FAR 91.303 definition as Aerobatic flight. I would never do this under full power with full deflection of rudder. I felt like many others that it may have been inappropriate to print this maneuver in "Rotorcraft". I can say I have watched many people perform this maneuver since about 1983 at Fly-Ins. I admit I started doing it (power idle, slow turn) about then also. I am not that technically qualified nor informed to say much more. I have read most all the post on this accident. I feel they are worth reading.