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Author Topic: Runway excursion at Cavanaugh Bay.  (Read 12073 times)

Bruce Byerly

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Re: Runway excursion at Cavanaugh Bay.
« Reply #15 on: August 01, 2019, 12:15:13 am »
Kent - neither stalls nor heavy braking should cause you issues. I think you will get comfortable if you keep working on it.    The harder you stop, the easier it should be to keep straight.

Stalls can and will end with a wing dropping sharply if you don’t keep the ball centered. But the rudder is very good at fixing it.

One thing I see causing new pilots problems is improper flight idle rigging and the consequent yaw as soon as the power levers hit flight idle, or about right at touchdown.   

donv

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Re: Runway excursion at Cavanaugh Bay.
« Reply #16 on: August 01, 2019, 12:25:35 am »
They do like to drop a wing in the full stall, even if you think you have the ball centered. There is lots of warning, though, so unless you are doing a test flight for some reason (as I was a few weeks ago) or you really want to, there is no good reason to do a full stall.

I went out and did some spins in my Citabria before doing the test flight, just to brush up a bit!

donv

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Re: Runway excursion at Cavanaugh Bay.
« Reply #17 on: August 01, 2019, 02:54:23 pm »
It would be nice to know if he ran off the end of the runway or the side. Maybe he was avoiding wildlife or something like that?

Bruce would know, but I would imagine at a minimum it would require a gearbox inspection. That's assuming the engine didn't cook itself.

I remember hearing many years ago about a 331 where the prop went into feather while it was at ground idle, and the temp apparently rose so fast that it way over-temped before the pilot could shut it off. I wonder if something like that happens in a case like this, or does the shaft shear or the gearbox fail, protecting the engine itself?

JMA

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Re: Runway excursion at Cavanaugh Bay.
« Reply #18 on: August 01, 2019, 03:52:30 pm »
Speaking of wildlife:
https://www.ntsb.gov/_layouts/ntsb.aviation/brief.aspx?ev_id=20190512X92801

Apparently, from what I am hearing, lost most of the horizontal stabilizer but was still flying.

Bruce you know about this one?  Had to go to S. America to find a whole new tail section for replacement.

donv

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Re: Runway excursion at Cavanaugh Bay.
« Reply #19 on: August 01, 2019, 05:13:33 pm »
I saw that... N51DM, too-- what a beautiful airplane. I hope they were able to fix it!

Bruce Byerly

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Re: Runway excursion at Cavanaugh Bay.
« Reply #20 on: August 01, 2019, 11:09:47 pm »
DM is getting a tail donated from some plane in Columbia.  But the fact it took off, flew around and landed safely is a testament to large surfaces and awesomeness of the planes! ;D

As far as prop strikes, it’s a tear down, inspect and replace as necessary program. There are various levels of inspection for various levels of prop strike and sudden stoppage. The way those blades shed, it may have kept running, I don’t know. Seems like every time those props come up, there some story or issue. Hope I’m wrong.

The 331 is pretty tough. Obviously sudden stoppage is not good but if the engine and accessories stop, the fuel stops and without fuel, you don’t have fire. I think what’s worse is bog down or situations where the fuel keeps coming while the flame front is back where it’s melting wheels down.

Adam Frisch

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Re: Runway excursion at Cavanaugh Bay.
« Reply #21 on: August 02, 2019, 09:21:16 pm »
I locked up one side of the brakes going into Corona during my training. That's a pretty tight airport. Left some skid marks, but got it under control. I have the soft brake option on mine, but not sure I like them. You can still lock them up, it just feels mushier, so not sure how much good they actually do.

But reversing seems to have its own set of problems. Wouldn't take that much of a malfunction for it to get out of hand if you're going into a tight strip and need to hit the reverse fast and hard. Probably takes a little experience to develop the muscle memory of which one to "reverse more" to counter a turn.

Anthony Chan in his 681 does a pretty good job of reversing more on one side to get her back on track in this clip:

https://www.youtube.com/watch?v=QMFqF0pDD8w
« Last Edit: August 02, 2019, 09:23:22 pm by Adam Frisch »
Slumming it in the turboprop world - so you don't have to.

Steve binnette

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Re: Runway excursion at Cavanaugh Bay.
« Reply #22 on: August 03, 2019, 02:14:08 pm »
Maybe Dons right he could have been avoiding something?  I hate to assume it is pilot error.

I also agree 100%with Don.  It is all about AS control.  This idea of shooting an approach at blue line seems crazy to me.  The idea that you should slow from vyse to 95kts when landing is assured, is asking for trouble IMHO.  It is an unstable approach

When is landing assured?  What is the benefit of flying a unstable approach like that.  The line forever has been “it is so you can GA in the event of an engine failure”.  In a Commander you can GA SE at any speed above VMC.  In fact in many airplanes you can.

My manual shows 93kts vmc, and  95kts vxse.  Those are based on max GW.  Vyse is listed as 113kts.  Why fly an approach up to 18kts faster than is needed..  Plus you will typically  be much lighter on landing creating even lower V speeds than those published in the flight manual.

I like 100kts on approach it is fast enough particularly when light and is slow enough to elimante floating.  Trying to slow at 200ft is destabilizing and creates issues that continue throughout the landing.

If the absolute worst happens and you lose an engine at DH and the runway is not assured, a GA is still the right answer.  You will dip below DH but that’s ok.  You will dip below DH on any go around.  It is baked into the numbers of a DH, remember it is not a MDA which is a hard altitude.  The only consideration is obstacles on the GA.  SE will impact that, but you will be climbing at vyse or vxse.  Those speeds are the best you can do.

Since I am ranting I will weigh in on braking :)

In an airplane with reversing props your primary braking is reverse thrust till you slow, then you transition to brakes. 

I have found it easy to start chasing the nose, on hard braking, if you jump on the brakes.  I am not sure if that is from the unique nose wheel steering on the TC or perhaps the big rudder.  I also have trouble keeping the rudder pedals neutral on braking.  Just too many years flying other airplanes.  I need to remind myself to keep the pedals neutral right before touchdown particularly if I plan on using max braking.  That really helps.

The first turnoff at my home airport CMA is short, maybe 1500ft from the end.  I practice max braking there and find I am usually slowed to taxi speed before the turnoff.  It is easy when using 100kt approach 95kt threshold and by keeping brake pedals neutral.  I also think most guys don’t use full reverse. It is really impressive to use the entire capability of the Commander.
« Last Edit: August 24, 2019, 10:49:00 am by Steve binnette »

donv

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Re: Runway excursion at Cavanaugh Bay.
« Reply #23 on: August 06, 2019, 03:52:55 pm »
Bruce, any idea which airplane the new tail came from for N51DM?

I'm always curious if it came from my dad's old airplane, 96008, which disappeared into the wilds of South America shortly after we sold it, and has never (as far as I can tell) been heard from again.

JMA

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Re: Runway excursion at Cavanaugh Bay.
« Reply #24 on: August 06, 2019, 04:16:40 pm »
Much like you DonV, I am always interested where the Jetprop's end up after they disappear.
Stolen/Drug Runners??? 

Not to be morbid, but not sure any other AC has this many 'illegal flight' crashes under its belt.
https://aviation-safety.net/wikibase/type/AC95

donv

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Re: Runway excursion at Cavanaugh Bay.
« Reply #25 on: August 07, 2019, 01:16:09 pm »
El Chapo approves!

Much like you DonV, I am always interested where the Jetprop's end up after they disappear.
Stolen/Drug Runners??? 

Not to be morbid, but not sure any other AC has this many 'illegal flight' crashes under its belt.
https://aviation-safety.net/wikibase/type/AC95

donv

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Re: Runway excursion at Cavanaugh Bay.
« Reply #26 on: August 21, 2019, 07:52:36 pm »
Looks like it flew out about a week after the incident! Good to see!

SKYFLYER

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Re: Runway excursion at Cavanaugh Bay.
« Reply #27 on: August 22, 2019, 09:36:25 am »
Wonder if that was on a ferry permit... Seems pretty quick repair for a new MT prop and engine inspection and whatever else it needed on the nose that far from a service center.

Will be interesting to see if it goes back into there again.

donv

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Re: Runway excursion at Cavanaugh Bay.
« Reply #28 on: August 22, 2019, 12:32:06 pm »
I'm sure that was a ferry permit... did you see the destination? Eagle Creek Airpark.

It's amazing what can be done in the field... a buddy of mine ferried a straight 690 out of a grass strip where the previous pilot had, rather unfortunately, gotten a little low (possibly due to clouds) and flown through some trees. We used to call that airplane "the woodchipper."

kent4142

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Re: Runway excursion at Cavanaugh Bay.
« Reply #29 on: August 23, 2019, 09:25:11 pm »
The engines are relatively easy to remove.  About 4 hours, and you have it in the back of a truck.  One man.  Installation maybe 8 to 10 hours, again 1 man.  So if you flew in, or trucked in a new prop and a loaner engine - one week sounds about right.

I am glad to see it out of Cavanaugh and getting squared away.  I hope we get to learn "the rest of the story" some day.

Total empathy and admiration for the owner and the machine!