C421 down near CA/NV border

[mshunter]

I dont jump into many discussions here, but I am dying to know on what basis you make this statement?

As a FAA DER Test Pilot, who has both intentionally and unintentionally spun multiple types of twins, there is nothing inherently impossible in the recovery, nor anything different from a single. Quite the contrary, I have never had an issue recovering, and never had it take me more than 1.5 turns, even from an inverted spin in a King Air. Power to idle, Ailerons Neutral, Rudder to conteract the spin, Elevator to recover. PARE.

I am also a 421 owner, and can not readily see how you get it into a spin from cruise flight. I look forward to learning what happened

The average pilot hasn't had any spin training. Let an airplane get slow, and develop into a spin, rather than just go incipient, and the recovery with all that extra weight away from the center of rotation become very diccifult to slow down.

Help me out her TwoTwoLeft. Your much better at explaining this than I am.

P.S. I'm a few drinks in right now, and probably shouldn't be trying to explain anything aviation.

 

[Bumblebee]

Unrecognized fire, subsequent structural failure?

meteorite?

 

[dustoff17]

meteorite?

Well, technically it would have to be a meteor......

 

[Jimflyfast]

I would just stop, drinks or no drinks. The weight of the engines is symmetric and doesnt enter the equation and has zero effect on spin recovery. Period. Unlike quite a few posters on the internet, I dont start posts with "I think". If I am going to post, I know. Not trying to be a dick, just trying to stop bad information

The question here is how does he get into a spin on a descent. I typically descend my 421 at 185-200 KIAS, which is pretty far from the 85-90 KIAS stall speed. You cant spin if you dont stall.

The average pilot hasn't had any spin training. Let an airplane get slow, and develop into a spin, rather than just go incipient, and the recovery with all that extra weight away from the center of rotation become very diccifult to slow down.

 

[mightynimbus]

http://www.kolotv.com/news/headline...Looks-for-Possible-Plane-Crash-207783261.html

 

[jmreii]

It's so saddening listening to the controller repeat his transmissions without a response and then after 5 all you here "spin"....scary stuff. So sad. EDIT: RIP

How do you allow an aircraft to get into a spin unless you place it there through improper use of the controls. The only spins I have perform where intentional and with a aerobatic aircraft. I was never taught to spin a aircraft anywhere else! You never really have the opportunity to observe a pilot's skill set until he or she reaches a jet aircraft.

 

[A150K]

How do you allow an aircraft to get into a spin unless you place it there through improper use of the controls. The only spins I have perform where intentional and with a aerobatic aircraft. I was never taught to spin a aircraft anywhere else! You never really have the opportunity to observe a pilot's skill set until he or she reaches a jet aircraft.

LOL wut?

 

[Inverted]

I would just stop, drinks or no drinks. The weight of the engines is symmetric and doesnt enter the equation and has zero effect on spin recovery. Period. Unlike quite a few posters on the internet, I dont start posts with "I think". If I am going to post, I know. Not trying to be a dick, just trying to stop bad information

The question here is how does he get into a spin on a descent. I typically descend my 421 at 185-200 KIAS, which is pretty far from the 85-90 KIAS stall speed. You cant spin if you dont stall.

The weight may not factor in, but P factor, asymmetric thrust etc will be a huge factor. Does the 421 use counter rotating props or is it a conventional twin? You can't spin if you don't stall, but you can stall at any airspeed. Who knows what exactly happened up there.

 

[Inverted]

I would just stop, drinks or no drinks. The weight of the engines is symmetric and doesnt enter the equation and has zero effect on spin recovery. Period. Unlike quite a few posters on the internet, I dont start posts with "I think". If I am going to post, I know. Not trying to be a dick, just trying to stop bad information

The question here is how does he get into a spin on a descent. I typically descend my 421 at 185-200 KIAS, which is pretty far from the 85-90 KIAS stall speed. You cant spin if you dont stall.

The weight may not factor in, but P factor, asymmetric thrust etc will be a huge factor. Does the 421 use counter rotating props or is it a conventional twin? You can't spin if you don't stall, but you can stall at any airspeed. Who knows what exactly happened up there.

 

[trafficinsight]

LOL wut?

My thoughts exactly.

 

[mshunter]

I would just stop, drinks or no drinks. The weight of the engines is symmetric and doesnt enter the equation and has zero effect on spin recovery. Period. Unlike quite a few posters on the internet, I dont start posts with "I think". If I am going to post, I know. Not trying to be a dick, just trying to stop bad information

The question here is how does he get into a spin on a descent. I typically descend my 421 at 185-200 KIAS, which is pretty far from the 85-90 KIAS stall speed. You cant spin if you dont stall.

Well you are doing a really good job of being a dick. Ever flown a V-Tail Bonanza with full tip tanks? They "wag their tail" even worse than one without, because of the extra weight on the tips, because of the extra inertia that it imparts on the airframe. Tourqe applied is torque applied. Kudo's to you for spinning a King Air. IMO, you're foolish and lucky to be alive.

Educate yourself, because with your attitude, I won't help you. It's great that you have spun airplanes that are prohibited to do so in. And I'm happy that you yourself own a 421. Great job flexing you internet muscle. I'll leave you a few links from what many consider to be the "source" on spins, causes, aerodynamics, etc. of spins. The are from Rich Stowell. He has been teaching EMT programs for enough years to really know what he is talking about. I worked with him for a few years, and learned a lot from him. As well, TwoTwoLeft taught/still teaches his program, which is why I tagged him in my previous post. I chose not to go into a long winded reply last night because it was late, and I had a few beers with friends at dinner, and I usually choose not to speak aviation when I have done any drinking. Read up, your facts are wrong. There are inertia forces, gyroscopics forces, and aerodynamic forces at work in a fully developed spin that can make it unrecoverable, in any airplane, even one certified for aerobatics.


http://www.richstowell.com/

http://ehfc.net/StallAndSpin.pdf

http://books.google.com/books?id=_4nGtx-_jHUC&pg=PA102&lpg=PA102&dq=does inertia effect spin recovery&source=bl&ots=J8rV4qJ0D5&sig=uLduSoz88qcaXU4Oh9fwc4qNH58&hl=en&sa=X&ei=w7WXUdyrKsKYqgHisoDoDA&ved=0CGAQ6AEwCA#v=onepage&q=does inertia effect spin recovery&f=false

Edit to add: I just realized you say you are a DER and have spun a King Air, inverted. How'd you keep it running, inverted, to enter an inverted spin?

 

[mshunter]

The weight may not factor in

Yes it will. It plays a HUGE role. In a fully developed spin, it can mean the difference.

 

[TwoTwoLeft]

How do we know it was a spin? We're relying on the pilot's interpretation of what's happening.

Most can't tell the difference between a spin and a spiral....

mshunter Hold on, my brain hurts already. I'm going to have to start form the beginning here when I get some more time....

 

[TwoTwoLeft]

The weight of the engines is symmetric and doesnt enter the equation and has zero effect on spin recovery.

The engines are symmetric relative to the aircraft's longitudinal axis. However, from what I've read and seen, the spin axis doesn't always line up through the longitudinal axis. Wouldn't the mass of the engines being farther away from the longitudinal or spin axis increase the angular momentum and reduce the effectiveness of the rudder input? Spin stage, aggravation, and CG would still major players in the speed of recovery too, right? Under controlled conditions does the extra rudder surface area of a twin solve this? What about fuel migration toward the wingtips of outboard tanks?


The concept is mass distribution. As you know the concept of "weight" is relative.

 

[MikeD]

Thanks for keeping it civil here. Continue.

 

[TwoTwoLeft]

Edit to add: I just realized you say you are a DER and have spun a King Air, inverted. How'd you keep it running, inverted, to enter an inverted spin?

The engines don't need to be running for it to depart normal flight... Negative airframe loads, altitude loss and having enough time to restart would seem to be some issues.

Jimflyfast
But yeah, I'm kind of wondering this too... Was it a 90/100 or 200/300? There's not much info out there about spin testing in light twins, let alone something the size of a King Air. How the hell would you even be able to bail out or install an effective spin chute that wouldn't significantly alter the CG or airframe?

 

[MikeD]

There are inertia forces, gyroscopics forces, and aerodynamic forces at work in a fully developed spin that can make it unrecoverable, in any airplane, even one certified for aerobatics.

In the T-38, I remember reading that while recovery from an inverted spin was rather quick and efficient, the resultant upright spin that you're find yourself in.....whether flat or oscillating.....there was no guarantee of recovery. Never tested it out myself though, although it has been tested.

In the F-117, you were pretty much losing the aircraft. There was no spin recovery procedure in the checklist, just a HIGH AOA RECOVERY procedure, and it was this:

1. Stick- Full Forward
2. Ailerons and Rudders- Neutral
3. AOA and Airspeed- Monitor [W- Maintain AOA between -8 and +9.5 during recovery]

If aircraft does not recover:
4. Stick- Maintain full forward and monitor AOA
5. Drag Chute- Deploy

If aircraft unloads (AOA below 14)
6. Stick- Neutral

If aircraft recovers:
7. Drag Chute- Jettison [Maintain AOA between -8 and +9.5 during recovery]
8. APU and Engines- Restart if required
9. FCS- Reset

If aircraft does not recover:
10. EJECT

Now, this whole procedure is really only recommended as best practice. Because truthfully, in this jet, you won't be recovering. Thats why this entire procedure is given with the overarching WARNING caveat, stated in Step 3, of the below:

"W- Monitor angle of attack to prevent either positive or negative angle of attack departure. There is no negative angle of attack limiting within the FLCC. A departure will result in loss of aircraft."

In other words, this procedure will most likely end at Step 3, and proceed directly to Step 10.

 

[TwoTwoLeft]

I'm not a test pilot or an engineer... I just get my knowledge from good books, the seat of my pants and hanging around the right people.

These are taken directly out of Sammy Mason's book "Stalls Spins & Safety"...

Thought this was interesting too..

 

[derg]

You guys do realize that you're debating a current flight test engineer, and former Boeing corporation flight test engineer?

Aye yi yi.

 

[MikeD]

You guys do realize that you're debating a current flight test engineer, and former Boeing corporation flight test engineer?

Aye yi yi.

Moi? Im simply tossing in two cents regarding what a couple of my particular former airframes had challenges with.