FlightmechH3
Pre-takeoff checklist
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FlightmechH3
Short, but very wide runway?
Learjet down at KMMU
- Thread starter Paul V
- Start date
Interesting video with some interesting information, apparently they got down to 85mph around 700ft, which at that altitude I would expect to see around 135-150 depending on weight.
Stall speed flaps 40 is going to be somewhere in the 95-100 knot realm, although the 45 series has allegedly very benign stall characteristics. You’ll get shaker 8-10 knots above the actual stall, so if 85mph isn’t a weird indication issue, at that point they were in a deeeeeeep stall with lots of voices yelling at them and stick shakers going off. Also worth noting that if the power is at idle and you’ve got full-flaps and gear down it gets very slow in a hurry, and it isn’t a super quick spool up time like a turboprop or piston.
On a normal approach a good sustained power setting is in the 55-60% range or thereabouts.
edit: Lear 45 series also have CVRs and FDRs so we should know at some point what was actually going on in the cockpit.
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TrueCourse
Line Up and Wait
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The airplane wasn’t going 85 mph at 700 feet. Is this what the youtuber above said? Speeds were much more normal than that, according to ADS-B data. It landed on centerline and was slowing below 100 knots before it took a turn off the runway. Last hit displays 73 kts.
Yep, he showed a comparison of the profiles between the lear and a flexjet that landed a few minutes prior.
TrueCourse
Line Up and Wait
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That YouTuber is using the Port Authority tracking website and it's the least reliable information I would look at when reviewing aircraft tracking. It displayed erroneous speeds in this case. He then makes some wrong assumptions based on that bad data, and should know that if it's going 85 mph at 700 feet it would have crashed well short of the runway. As mentioned earlier, based on ADS-B data, the approach speeds appear normal and consistent all the way until touchdown. The early part of the touchdown rollout appears normal on centerline with deceleration, so it appears that whatever went wrong did so, after this.
I would guess that it could have been a NSW issue in that case. If you don’t catch it immediately you’re going off the side.
He also makes an assumption that simply because one pilot jaded a bit of a humorous comment to the controller, that so how it translates(or is strongly implied to translate) into not focusing on the approach properly and not maintaining a disciplined cockpit. Completely unprofessional on the YouTuber to suggest that with no actual evidence. A CVR transcript, if there is one, will be likely be able to determine that.
This is what happens when these guys analyze in the way they do. I saw Juan the other day analyzing a DC-3 crash stating that it was a takeoff when other websites called it a landing.
I don’t put much credibility in these guys unless they have some actual inside info.
This is what happens when these guys analyze in the way they do. I saw Juan the other day analyzing a DC-3 crash stating that it was a takeoff when other websites called it a landing.
I don’t put much credibility in these guys unless they have some actual inside info.
Fearless Tower
Touchdown! Greaser!
Interesting albeit anecdotal thing I’ve noticed over the years is steering issues/faults alarms seem to be the most common reason for the 2 Lears our local shop has maintained to be stranded on the road.
The flight crew has had to abandon their Lears and airline home more often than my 60 year old Beech 18 in the last 6 years. Granted they fly a lot more hours, but still….