ooops in tuscon

The first post - yesterday’s incident at Sun Valley-Bison-Fort Mohave Airport - that’s not near Tucson. The more recent Marana crash, that’s near Tucson (and unfortunately it sounds like that may have been a bad one).
 
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Runway 12/30 was closed at the time.

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I had to look it up as I’d never heard of Sun Valley, Bison Fort Mojave. We call it Bullhead City which is closer to Vegas than Tucson.
 
Hmm, being at 112 knots groundspeed and 450 feet above runway elevation crossing the threshold... It is not a great surprise that did not work out.

I have not checked the weather at the time of the accident, but the fact that he choose the shorter runway probably means that winds were favoring that one. Which might would increase his TAS, and would mean he was outside of flaps speed.
 
Timbeck2 said:
I had to look it up as I’d never heard of Sun Valley, Bison Fort Mojave. We call it Bullhead City which is closer to Vegas than Tucson.
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That's IFP. Sun Valley is A20. It's a cute little airpark.
 
dcat127 said:
Hmm, being at 112 knots groundspeed and 450 feet above runway elevation crossing the threshold... It is not a great surprise that did not work out.

I have not checked the weather at the time of the accident, but the fact that he choose the shorter runway probably means that winds were favoring that one. Which might would increase his TAS, and would mean he was outside of flaps speed.
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The accident was at 0010z

The wind was calm to light and variable, to favoring the north, per the METARs around that time.

Closest one:

KAVQ 090015Z AUTO 00000KT 10SM CLR 33/M04 A2980

An airport elevation of 2032 makes for a density altitude of ~4600’ at the surface in those conditions. That’d impart about 7% additional TAS to any given CAS. In a calm wind, 112 knots GS over the numbers would be about 104 indicated at that density altitude.

The ADS-B reported altitude of 2200’ over the numbers given a local altimeter of 29.80 could be closer to 2080’ absolute (and presumably indicated) altitude, but the resolution we see is in 100’ increments, so +- 50’ to that.

The runway 3 threshold is displaced 494’ for an LDA of 3398’. A two-box PAPI serves the runway, set at a 2.91° glidepath and a TCH of 53’.

With a TDZE of 2026 on that runway, the accident airplane may have crossed the threshold on the nominal glidepath at roughly the designed TCH (2026+53=2,079), but back to the +-50’ due to lack of resolution.

It also could be noted that the last pattern was fairly tight, downwind was not parallel - it converged and left a very tight base. It looks as if they turned about 1/2 mile final and overshot, which could have complicated things that followed.
 
This also came at the end of a 10-hour day originating at KSGF with 60 and 75 minute stops (not including presumable startup and taxi time) at KELK and KJTC, respectively.

Local time was about 5:10 PM. Local sunset was 6:49 PM. The sun would have been around their 7:00 to 8:00 position when they were on final, about 20° above the horizon.
 
NTSB Preliminary for N4190E

After slightly overshooting the final approach course, the airplane adjoined the leg about 3,200 ft from the runway threshold while maneuvering at 130 kts. The airplane’s airspeed temporarily increased to 135 kts and then decreased, reaching 116 kts as the airplane crosses the runway threshold (see figure 2 below). The airplane touched down an estimated 1,500 ft from the runway threshold and bounced back airborne several times. The ground speed decreased to 80 kts with about 1,300 ft of runway remaining and continued to gradually decrease reaching the end of the runway surface at 54 kts. The last recorded speed of about 44 kts was adjacent to the accident site.
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The report is fairly clear he was flying sloppy, fast traffic patterns. Something you really cannot afford to do in a Saratoga on a relatively short runway.

But is there something else going on here? When not attempting a short landing I typically cross the threshold at about 85 kts and consistently make the first turnoff at 2200 feet without max braking or any special technique. I'm fairly sure that if I was on the ground at 80 kts, I could get stopped in 1300 feet, or at the very least I would be slower than 54 kts after 1300 ft. I don't see that the report comments on flap position or throttle settings. But I'm wondering, were there additional factors such as he still had partial throttle? Or no flaps? Or?
 
Appears he should have also been flying right traffic to runway 3.

The tepid deceleration is puzzling. Report noted lack of any main gear marks until 265 ft before the end of the runway. I guess we can assume the aircraft stopped bouncing by the 80 kt groundspeed point?

Satellite pics show the concrete drainage culvert has a 150 ft wide bridge in line with the extended runway centerline such that an aircraft in overrun should pass cleanly over the culvert. However, the report notes that a few hundred feet before the end of the runway the aircraft veered to the right, which would seem to indicate the aircraft avoided the intended non-destructive overrun path and instead hit the culvert embankment coming to a rapid, destructive stop.
 
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