Incredible landing after hail damage

[RooFlyer]

An amazing safe landing after windscreen shattered and nose cone destroyed. (Paywalled - Google "Cricket ball-sized hail strikes plane")

A pilot has been decorated for landing a passenger jet safely during a storm in Istanbul despite giant hailstones having smashed the aircraft’s windscreen.


Pieces of ice the size of cricket balls cracked the coughpit windshield of Captain Alexander Akopov’s Airbus A320 jet as he brought it in to land at Ataturk airport in the city on Thursday evening, with 127 passengers and crew on board.

A photograph taken shortly after the aircraft landed shows its nose caved in and the windows so damaged that it would have been almost impossible to see through them. Its autopilot mechanism was also knocked out.

 

[jb747]

I wonder what the engines look like?

 

[theweaselsteve]

Video of the landing

[video=youtube;JJPGTgYrLzQ]https://www.youtube.com/watch?v=JJPGTgYrLzQ[/video]

 

[moa999]

Cricket balls, not golf balls

 

[ftm]

Video of the landing

[video=youtube;JJPGTgYrLzQ]https://www.youtube.com/watch?v=JJPGTgYrLzQ[/video]

Wow. That looked like it was on fast forward!

 

[Quickstatus]

What landing aids would have been available in this situation with a inoperative AP?
Apart from Radar what else is in the nose cone? Glideslope and localiser antenna?

How would they know what the size of the hail was while flying at 400kts?

 

[jb747]

What landing aids would have been available in this situation with a inoperative AP? Apart from Radar what else is in the nose cone? Glideslope and localiser antenna?

First question is 'why was the AP inoperative?'. That could imply a loss of valid airspeed or angle of attack/sideslip information, with a resulting law change. I think the ILS would have still been available, as the aerials are on the lower fuselage and gear doors. But the landing appears to be out of a turn...

There doesn't appear to be much, if any, flap involved in the landing either.

GPS..if they have it.

How would they know what the size of the hail was while flying at 400kts?

You wouldn't know the size, or even if there was any hail, but I'd expect the cell producing it to have presented a pretty radar return...

Much more to come on this one, I think.

 

[Quickstatus]

Here she a facsimile: not sure if accurate
Suggests that ILS aerials may be in or near nose cone.
If so possible that precision aids not available.
Down to VOR/DME?. GPS/RNAV?

Certainly not wings level at final - does appear to be out of a turn which suggests a non ILS approach. Was approach unstable?

 

[jb747]

Here she a facsimile: not sure if accurate
Suggests that ILS aerials may be in or near nose cone.
If so possible that precision aids not available.
Down to VOR/DME?. GPS/RNAV?

Certainly not wings level at final - does appear to be out of a turn which suggests a non ILS approach. Was approach unstable?

Sadly your picture won't magnify for me. I would expect the localiser to be under the top of the radome, which is still intact, and g/s to be on the bottom of the fuselage just behind the dome. So, it might work, but hard to say.

Approach stability isn't really an issue in this case...you just do the best you can. Discussion on pprune indicates that a number of aircraft were hit, with this one being the worst. Also that multiple aircraft were declaring min fuel, so overall pretty messy.

 

[Quickstatus]

Apparently Pilots were able to have some sort of visual out of side-windows

Here is a better facsimile



UR-AJC IST-ECN (Turkish cyprus) diverted to IST (27/7/17)



DL1889 BOS-SLC diverted to DEN in 2015:

 

[docjames]

The question that arises to me is: what were they doing flying through a flock of hail in the first place.....

 

[jb747]

If you pull up the flight on FR24, and have a look at the track and data, finals is particularly interesting.

 

[Quickstatus]

The question that arises to me is: what were they doing flying through a flock of hail in the first place.....

There is suggestion via other media sources that the radar did not reflect the hail.

 

[jb747]

The question that arises to me is: what were they doing flying through a flock of hail in the first place.....

Radar shows moisture. Hail doesn't necessarily show up at all. You'd expect the cell producing it to show up, but the hail won't necessarily be at the cell. It could be quite some distance downwind. One of the comments on another forum was from someone who claimed to be flying there at the time, and he said that nothing that was being displayed on radar was particularly nasty looking.

 

[RooFlyer]

If we say 'radar shows a contrast in density', then even though ice is less dense than liquid water, I would have thought a severe hail storm would give enough reflectivity to look substantial - ie more so than moderate, perhaps even heavy rain. Although if there the hail stones were large but relatively thinly spread, I guess the radar cross section would be small. Or maybe the hail gets masked by the rain in front of it?

Might the radar in airplanes be 'tuned' to rain type signals and therefore mis-display hail?

 

[jb747]

Radar doesn't see everything. Perhaps you should consider hail to be the stealthed version of rain.

 

[Quickstatus]

Radar is not about contrast in density but rather degree of reflectivity (AFAIK)

Radar jamming chaff is highly reflective. Water is much more reflective than ice.

This aircraft was in climb when it encountered a region of hail.
When an aircraft is in climb and maybe turning at the same time does it fly into the region of air in which it is pointing?
Im guessing the radar is reflecting back from a region where the radar is pointing - therefore where the nose is pointing but due to manoeuvres (climb, turn) the aircraft may enter a region that has not been "radared" therefore the screen is black because no radar reflections were received?

 

[Quickstatus]

If you pull up the flight on FR24, and have a look at the track and data, finals is particularly interesting.

The passengers would have perceived the plane "diving" at one stage. The pilots dumped -5000ft in 2 minutes in the latter stages but then came in "hot" at 165kts instead of usual 125kts. I guess they wanted to line up the aircraft right the first time.

 

[jb747]

When an aircraft is in climb and maybe turning at the same time does it fly into the region of air in which it is pointing?

The radar antenna scans left and right continually. Some also scan vertically. Unless it's a radar that uses a database for its display (380), the image normally degrades in turns, but you should have had plenty of time and scans before any turn to ensure you're going into a clear area. Climbing and descending makes no practical difference.

Having said that, my guess as to the position of the strike is just after the right hand turn at about 15:50Z.

The passengers would have perceived the plane "diving" at one stage. The pilots dumped -5000ft in 2 minutes in the latter stages but then came in "hot" at 165kts instead of usual 125kts. I guess they wanted to line up the aircraft right the first time.

5,000' in two minutes is 2,500 fpm. You'd see that on most descents. A combination of high speed and speed brake will give up to about 6,000 fpm, with the nose still within 5º of the horizon.

There is no relationship between the speed on approach and 'being able to line up'. If anything, faster gives you less opportunity to correct any errors. In any event, they weren't lined up. That also implies the loss of ILS, and possibly a law reversion as well.

In this instance I'd read 'faster' as meaning the aircraft is possibly not configured with the normal landing flap (3 or 4), and the video seems to show that.

The speed is all over the place on finals. Granted, there aren't many data points, and we aren't seeing the IAS or TAS, just G/S. It's possible that the conditions are causing the G/S changes. Nevertheless, it all makes me wonder what IAS displays they had...if any.

Certainly from what I can see, it looks like a nasty hand, well handled. The report will make very interesting reading.