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This video is making its rounds on social media claiming to show a 90 degree vertical take off:

enter image description here

One can not tell from the video alone what the angle is.

  1. Does anyone have a third party reference for the actual angle for this video?

  2. What is the maximum angle for a Boeing 737 MAX with typical passenger load?

  3. What is the maximum angle for a Boeing 737 MAX especially configured to maximize the angle?

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Actual angle is 30 degree not 90 ! As this written in original video description

View from the side

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    $\begingroup$ Even in the original clip you can't see the front of the vertical tail in the climb and that is about 50deg, so you know it is nowhere near 90deg. $\endgroup$ – Pilothead Aug 4 '18 at 17:09
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That’s a wild demonstration but it’s also not a very realistic barometer performance for typical 737 operations. The video you see there is a high-performance demonstration flown in an air show or a trade show just for the purposes of entertainment. It involves an airplane that has literally been stripped down of any unnecessary parts, no other personnel or cargo on board except for the minimum required flight crew and barely enough gas to get the performance done and maintain day VFR reserve minimums to get them back to the airport. The climb there was done in about an angle of 50 to 55° from the horizontal. Even in these conditions a Boeing 737 does not have a thrust to weight ratio exceeding one and as such the aircraft is in fact slowing down. Still it gives an impressive climb to around 2000 to 3000 feet above the airport for the spectators below.

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    $\begingroup$ I don't think it's really been "stripped down", it just has minimum fuel and payload. $\endgroup$ – fooot Dec 4 '17 at 1:57
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    $\begingroup$ It is stripped down. They’re removing virtually everything they can out of that airplane to keep it as light as possible in order to maximize performance. $\endgroup$ – Carlo Felicione Dec 4 '17 at 7:58
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    $\begingroup$ The plane does have a day job of doing flight testing, the performances are just a side gig. I think it has the full interior installation, but even if it doesn't, it has a bunch of flight test equipment which may end up being heavier. $\endgroup$ – fooot Dec 4 '17 at 16:36
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    $\begingroup$ Pictures of the interior $\endgroup$ – fooot Dec 4 '17 at 16:41
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    $\begingroup$ There is no need to strip it out for performance. The base model has 60,000lbf thrust pushing 90,000lb plus fuel and payload, so it has a very high thrust to weight ratio to start with. It wont do a vertical climb and still accelerate, but given a bit of room to build up some speed, it it can put its nose a long way up and keep it there. Just because it can be very fuel efficient, doesn't mean it must be! $\endgroup$ – Paul Smith Dec 4 '17 at 22:39
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We can find some estimate of the angle from the video, at least at certain instants. The wingspan of a 737 Max is $W = 35.92m$ The length of a 737 Max 7 is $L = 35.56m$ (assuming this is the correct model). We can see how that ratio evolves.

When you measure on the video at 0:55 (where the plane seems the most vertical, and with no apparent skewness as both wings are symmetrical), you have $W_{vid} = 7.8cm$ , and $L_{vid} = 4.8cm$ (on my screen), which is a totally different ratio because the plane is inclined.

So from the camera's perspective, the inclination angle at that moment is $asin(L_{vid}/W_{vid}) = 38deg $

To have the inclination with respect to the ground, you would have to add the camera's own angle with respect to the ground, which we don't know at that instant (could be 10-15 degrees, which would give an inclination within the range given by @carlo-felicione).

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