Monday, February 22, 2010

Nose Gear Collapse Tutorial

Here's a fascinating example of why I love the Net and how it can affect our lives for the better.
Surfing around for LSA tidbits to share with you, I came across an excellent YouTube video.

The poster (mikehoverstreet) spent a fair amount of time crafting this thorough Anatomy Of An Incident discourse, including a scrolling commentary on post-crash theories as well as his ongoing uncertainty about why the accident happened.
There are multiple benefits for us here:

* The pilot's no-ego willingness to take responsibility in the service of greater understanding, (even though many commenters place blame on the instructor!)
* Multiple observations and postings that serve up a consensus on the actual cause
* The value of sharing insights - both in the vid itself and in the many comments, most of which were clearly posted by experienced pilots.

My challenge to you: After you've seen the video, but before you read the comments posted below, study the crash and the slo-mo versions again until you have your own theory as to what happened.
Then read the comments.
Do they jive with your own conclusions?
Were you surprised?
In the pre-web past, how else would we have learned from this incident, unless we read it in an article or were one of the fortunate few in this pilot's circle of acquaintances?
Viva la Internet!


Ed said...

The video focuses on a stall but I don't see it. I see a nose wheel contact at a low pitch attitude.

Anonymous said...

Did the wing stall or only the stabilizer. If the tail stalls then the airplane will pitch down uncommanded and the stick force will get light. The airflow under the tail in the flare may deflect the wing downwash onto the horizontal tail with flap deflection.

CT had a similar problem and changed the CG limits until the longer fuselage LS model. The 2005 CT has a more forward limit. After that version you need ballast to fly full fuel solo. CG to far forward.

Doug said...

I've found that many airplanes have better flying qualities near the aft CG, and the CTSW is just one of them. Ballast is cheap (empty 2L bottles full of water or sand) and simple to use.

The biggest lessons in here for me are (1) the approach seemed high and fast, probably leading to extra speed and distraction and (2) the nosewheel is a fragile thing needs to be kept off the ground as much as possible.

Capt. Scott said...

I watched the video several times. The airplane did not stall.

The pilot flew it into the ground.

Depth perception and that last two feet is what got you.

John said...

Aircraft flying handbook chapter 8 has a lot og onfo on faulty landings. I dont see how to save it after that first bad strike because the second came up very fast.

Anonymous said...

I agree with scott, what I first saw was the pilot flying it to the runway with no flare at all.

Mike Hawkins said...

I've done this twice. Ouch! I doubt very much whether your airspeed was too slow - if anything the reverse and you hit the ground with airspeed to spare.

It looked to me as though your approach was high and you were 'aiming' for the runway. I had to conclude from my own flying errors that

1) I was trying to land the aircraft instead of trying not to land it (!)

2) I am used to landing on grass strips and I suspect that a wide, dark tarmac runway made me think I was closer to the surface than I was.

3)I had more time than you from first bounce to second, so why didn't I immediately apply power to re-organise myself or go round?

4) You don't mention altitude or temperature at the time of the incident. We landed (I was not the pilot) two-up in a CTSW in The Alps last Summer at an altiport at 4500ft in warm weather and close to the MTOW and the marked descent speed was well noticed and controlled by the pilot but we still landed in a business-like fashion!

5) I now have 300 hours in a CT2K and feel I should know better but I don't think I have realised how necessary it is to have the stick all the way back at the time of touching the ground. Perhaps the authority of the stabilator isn't as good as some other designs of aircraft.

I thought I would fly something else but one flight in my CT on its return on both occasions and I thought: 'No. This is still the one!'

At present I am landing it with the grace of a swan. I am, of course just a duck in disguise and no-one can see how hard I'm paddling under the water.

Well done on accepting responsibility - the first and most important stage in making yourself a better pilot.

Well done and good luck!


Dave said...

A nose wheel's only purpose is for steering while ON the ground. Main gear is so named for that purpose and every touch down needs to begin on the mains...and instead of "driving" to a landing, one must fly and flare so the mains touch first...Unfortunately flight instruction has been lulled into complacency about this with fairly rugged nose gears of spam can Cessna's and Pipers....

Anonymous said...

The student pilot in this case does not know what a stall is. To make reference to the ASI and say the airplane should not have stalled is wrong.
A stall occurs when the smooth airflow over the airplane’s wing is disrupted and the lift degenerates rapidly. This is caused when the wing exceeds its critical angle of attack. It can occur at any airspeed, in any attitude, with any power setting.