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Old 11th Mar 2017, 05:35   #21 (permalink)
 
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Real or not it's just a matter of time before there's an accident here, the number of
approaches significantly below a normal glidepath in order for a few idiots to 'show off'
makes it inevitable.
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Old 11th Mar 2017, 06:43   #22 (permalink)
 
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Quote:
Originally Posted by Capn Bloggs View Post
If you're implying that it was an all smooth and dandy 3.15 approach, FR24 tells a completely different story.
No, it doesn't

(apologies, mods, for the size of the image, which shows each of the two approaches, from roughly 2500' Mode C at the extreme left)



If there's more than 50-75' difference in the heights at any given point along the respective approaches, then that's not supported by the data.

Quote:
Rider: I'm not implying anything about the accuracy of FR24, merely pointing out what appears to me to be poor/misleading interpretation of the FR24 info.
Yours is the poor/misleading interpretation - neither you nor I can deduce absolute heights AMSL from the data without knowing whether or not it has been corrected for QNH.

All you can do with the data is compare the values for the two approaches (see above).
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Old 11th Mar 2017, 06:47   #23 (permalink)
 
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I'd be very careful trying to infer any height from a picture.

Many years ago I took some air to air shots of our aircraft. With the telephoto lens foreshortening perspective and the light it looked like the aircraft was skimming the surface. we actually thought twice about publishing the image to avoid awkward regulators questions.
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Old 11th Mar 2017, 07:42   #24 (permalink)
 
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Quote:
No, it doesn't
Yes it does. Drag the aeroplane symbol along and you'll see that that approach was nothing like 3.15 from 3000ft as you stated in your earlier post with the implication there was nothing wrong with it. It is clear that the first approach was above and then ducked down below the path of the second approach. Perhaps you are not a pilot. Gyrations in sink rate including 1200fpm at 300ft is not normal. If you discredit that info, then your claim of 3.15 from 3000ft is also discredited.

As for
Quote:
Yours is the poor/misleading interpretation
That's why I stated "Rider...".
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Old 11th Mar 2017, 08:28   #25 (permalink)
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pilotmike
Have another look at the article.There is a second picture of the same 737 aircraft with a caption which says the picture is of the second approach.It's the 3rd picture from the top.
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Old 11th Mar 2017, 09:27   #26 (permalink)
 
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Yellow line (rh pic) crosses extended centerline at 0.33 nm, both yellow lines follow the line of sight of the telelens.
I'm pretty sure about that, based on 2 landmarks that match both on telelens & on sat picture.
I guess the picture was taken from the Sonesta Maho Beach resort, from around 8-10th floor.
I leave it to the brighter spirits to draw any conclusions (or not if they are really bright).
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File Type: jpg WestJet SXM.jpg (109.5 KB, 241 views)
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Old 11th Mar 2017, 09:51   #27 (permalink)
 
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Quote:
Originally Posted by Capn Bloggs View Post
Drag the aeroplane symbol along and you'll see that that approach was nothing like 3.15 from 3000ft as you stated in your earlier post
Here, for the geometrically-challenged, is the FR24 data plotted relative to a nominal 3.15 approach.



The blue diamonds represent the first approach and the magenta squares the second one. Clearly an unquantified offset (based on the unknown QNH) needs to be applied to the two sets of data, otherwise both aircraft are in the sea short of the runway.

Yes, the first approach was lower than the second one by around 150' at about a mile from the threshold (so I stand corrected on my earlier 50-75' estimate), but the claim that the first approach was "nothing like 3.15 from 3000ft" is nonsense.
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Old 11th Mar 2017, 09:54   #28 (permalink)
 
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Quote:
Yes, the first approach was lower than the second one by around 150' at about a mile from the threshold
Quote:
but the claim that the first approach was "nothing like 3.15" is nonsense.
Are you even aware of the significance of a difference of 150ft at 1nm final??
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Old 11th Mar 2017, 09:57   #29 (permalink)
 
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Quote:
Originally Posted by Capn Bloggs View Post
Are you even aware of the significance of a difference of 150ft at 1nm final??
Yes, the words "too low" spring to mind. What's your point ?
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Old 11th Mar 2017, 10:38   #30 (permalink)
 
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Elaborating at bit further on DaveReidUK's hard work (without the author's permission )
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Old 11th Mar 2017, 11:39   #31 (permalink)
 
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https://m.youtube.com/watch?v=yNhAYKM-7LQ&feature=youtu.be

I guess at SXM there's always more than one camera 👍🏻
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Old 11th Mar 2017, 11:46   #32 (permalink)
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@ Climb360...

Well that takes care of that... So much for those that accused the photographer of manipulating her picture...

Yes I'd say that was a close call!
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Old 11th Mar 2017, 11:51   #33 (permalink)
 
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Speechless.

Someone's in trouble.
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Old 11th Mar 2017, 11:54   #34 (permalink)
 
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That YouTube video helpfully includes the TCNM METAR at the end.

A QNH of 1019 would indicate that actual heights AMSL will have been approximately 150' greater than the Mode C values.
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Old 11th Mar 2017, 12:06   #35 (permalink)
 
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Hmmm. The YouTube video shows, toward the end, a couple of stills and offers them as "proof" that the sky was about to fall in etc. The snag with this is the aircraft was further out when showing the second approach. Just look at the comparative sizes of the aircraft in the 2 stills. The second shot (missed approach) was taken when the aircraft was closer to the camera.
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Old 11th Mar 2017, 12:07   #36 (permalink)
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To me it looks like he is within a half wing span (~ 113') from the water, so about 60 feet?
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Old 11th Mar 2017, 12:10   #37 (permalink)
 
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Quote:
Those approach plates might not be the ones WestJet was using, they are from 2003
Those were the first decent Google search results.
In any case, good enough to prove a point.
Why people insist on using unverified data from a flighttracking website and present it as the gospel is beyond me.
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Old 11th Mar 2017, 12:15   #38 (permalink)
 
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Perhaps there was some windshear involved? Othewise it's quite hard to explain why the plane descended so low while supposedly being visual with the RWY. But then again, so was the Asiana 777 in SFO...
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Old 11th Mar 2017, 12:30   #39 (permalink)
 
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OK, so they were a tad low (for reasons unknown to us). They did the right thing and went around for another go. They were never close to crashing. Just a lot of hype by people looking for a story to pep up a boring day. I have spent time watching approaches at SXM and seen Cessna C208 Caravans of FDX just as low....and continue to land.
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Old 11th Mar 2017, 12:37   #40 (permalink)
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@ Hotel Tango...

Won't argue with you about the missed approach part, they did the right thing but they were more than "a tad low" IMHO... The question we are asking is why?

There is nothing wrong in trying to find out why they got in that position where the aircraft was in an unstable condition at such a low altitude and I hope TC gets involved to get to the bottom of this.
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