Another Citation CJ4 crash...

JJ429PA said:
Magnificent airplanes, but they REALLY don't like runway contamination. Clean & dry runway, you can roll it on nice and stop under 3000' no sweat. Wet and I don't like anything shorter than about 4500'. Snow/ice, etc and the book numbers go up exponentially to where you might as well just let it roll to a stop on it's own. Interestingly, the penalty for inop ground spoilers is something like a 0.03 factored landing distance (in the CJ3 at least). They don't help as much as you'd think.
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Could be worse...at least no brake-by-wire...
 
pwttogfk said:
Could be worse...at least no brake-by-wire...
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I've stopped a Phenom 300 near MLW in less than 1500'. Brake by wire (combined with carbon brakes) does have advantages when pilots understand it (and don't freak out on a contaminated runway and yank the emergency brake, removing all the protections, at 100+ knots). I'm continually surprised by the number of people who still don't understand a tire aggressively riding the edge of skid is better for stopping than a locked up tire.

These planes (big CJs, Phenoms, etc) are some of the largest ones using single wheels on the main gears. Relatively small and high pressure tires (less surface contact area), single brake units, etc. push the brakes more than a dual wheel unit. The brakes are so effective when dry it can build a lot of confidence in the units, but the limitations need to be respected with any contamination.

Embraer provides some rules of thumb (percentage increases) for little things...a few knots fast, a few feet high, a slight delay in brake application, etc. Suddenly a 2500 ft landing distance is approaching 6000. I've yet to see anyone with passengers on board smack it on at the thousand footers and go maximum braking before the nose hits the ground.
 
JeppUpdater said:
I've stopped a Phenom 300 near MLW in less than 1500'. Brake by wire (combined with carbon brakes) does have advantages when pilots understand it (and don't freak out on a contaminated runway and yank the emergency brake, removing all the protections, at 100+ knots). I'm continually surprised by the number of people who still don't understand a tire aggressively riding the edge of skid is better for stopping than a locked up tire.
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I always hear the same thing from Phenom drivers: "Awesome airplane! But the freakin' brakes...." I have no doubt the technology is soundly engineered. The hurdle is getting meatbags to re-learn their braking technique. It's always sounded like a needlessly over-engineered component. A digital Brake Control System with artificial pedal feedback that applies brake pressure on a curve and will lose it's mind if you reduce pedal pressure at any time during the event. It seems like a nice system when it works and the pilot works with it, but barreling down the pavement at 100 knots trying to slow down and keep the centerline in a crosswind...that muscle memory can be a tough horse to tame in the moment.
 
JJ429PA said:
A digital Brake Control System with artificial pedal feedback that applies brake pressure on a curve and will lose it's mind if you reduce pedal pressure at any time during the event.
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I think if they had gone with heavier pedal springs (there is no true feedback, just spring pressure, and not much at that) there would be less complaints because the brakes would feel more 'normal'. As you mention, muscle memory is a rough thing and when you've done it the same way since the Cessna and Piper days it's hard to brake that habit in a pinch. I will say I'm a firm believer in the technology and realistically it's only going to be more prevalent as time progresses...hopefully companies will push for a more traditional feel. I drive a year old truck with fully electronic brakes and you would never know, it feels identical to a standard brake system, complete with pulses if the anti skid kicks in. The technology is there.
 
dustoff17 said:
Did he seriously say that? Please tell me that's not a quote!!
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It's in the OP article ... including this gem ... "There's an airplane at the end of the runway waiting to take off," Zeliff said. "I assumed there was ice, OK, but I didn't think it would be bad because of that little plane."
 
Murdoughnut said:
It's in the OP article ... including this gem ... "There's an airplane at the end of the runway waiting to take off," Zeliff said. "I assumed there was ice, OK, but I didn't think it would be bad because of that little plane."
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Thank you, I missed that gem. What a tool!
This guy related to Rousch by any chance?
 
"I assumed there was ice, OK, but I didn't think it would be bad because of that little plane."

I'm sure that acknowledgement won't come back to bite him...
Great reminder not to talk to the press.
 
Murdoughnut said:
"They said I did everything right," Zeliff said. "They actually said they wish more pilots would fly like I do."

o_O
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My reaction was all like ...

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Champcar said:
ATP's are just as if not more capable of crashing that Private Pilots.
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It's a question of likelihood, not capability. And what on earth makes you believe an ATP rated pilot is "more capable" of crashing than a Private Pilot?
 
KOZW. Not the longest runway, completely surrounded by 40 ft plus trees. Deer seem to like the runway. Great Michigan airfield run by some great people.
 
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