For the aviation fans

[kosmonooit]

According to the Blanco they came in hot, the wind had shifted and  was gusty, they were just about to switch landing direction. Should have / could have Gone Around?

[Spokey]

According to the Blanco they came in hot, the wind had shifted and  was gusty, they were just about to switch landing direction. Should have / could have Gone Around?

Yeah, I just watched the update. I like his presentation.

https://youtu.be/XReQNKbIkdw

[Spokey]

Locally on a DRY runway, guys are fine with 7/8 knot tail win . Turkish flight that runway wasn't just wet, looked like it most likely had standing water as well

Latest on ZsCAR. Is that they might have had a catastrophic airframe failure, which led to the crash.

Yup, I am happy to land up to 10 kts TW in dry (runway length dependant of course). And agreed, on looking at the video, that looks like a Contaminated runway, more than 3mm of water. Compounding their problems.

 

Very sad to read of possible catastrophic inflight failure of ZS CAR. I still do wonder at that. I have to have trust in engineering and maintenance, unlikely that aeroplanes just fall apart. But it has happened I guess and then likely weather or poor maintenance related. Could also be as a result of pulling hard g in a terrain avoidance manouvre. I hope the investigators get to the bottom of this. Comment has ceased on AVCOM.

[eddy]

Must have been a very hard landing. I thought they usually land against the wind? Could landing with a tailwind have caused a sudden drop during the landing?

 

No, not a hard landing. As Spokey has said, a  fast one and he couldn't stop before the end of the runway. The damage was caused as he was still travelling at about 115kph when he got to the end of the runway and crashed into a wall further along.

 

Spokey also spoke about the effect of a tailwind on stopping but let me try and answer the question differently and explain in layman's terms and very simplified, WHY this is so.

 

There is a minimum airspeed for each aircraft below which the wing will stall and stop flying. Lots of things affect the stall speed, but for the purposes of this explanation consider it a constant. The landing speed of an aircraft takes the stall speed and adds a margin to that to ensure the plane flies all the way to the landing.

 

 

Now, if there is zero wind and the plane moves through the air at 100kt, it is also moving over the ground at 100kt.

 

If you are moving through the air at 100kt but you have a tailwind of 30kt you are moving across the ground at 130kt. Lekker when you are cruising: comfortable through the air, but fast to your destination.

 

Conversely, if there is a 30kt headwind, and you maintain a airspeed of 100kt, you are travelling over the ground at only 70kt.  i.e. Fast through the air, but nice and slow over the ground- which is what you want when you are landing.

 

 

Remember,  until it has landed the airplane does not care how fast it is moving over the ground, it is air moving over the wings that stops the wing stalling and keeps the plane aloft. However, once you are on the ground groundspeed becomes crucial as  you want to be as slow as possible because you ultimately need to stop.

 

Stopping a plane travelling at 130kt as opposed to 70kt is obviously a different proposition and therefore a plane typically lands into the wind because in addition to the lift provided by the plane's forward movement through the air,  the wind moves more air over the wing allowing you to remain airborne but land at the lowest groundspeed.

Edited February 7, 2020 by eddy

[Spokey]

No, not a hard landing. As Spokey has said, a  fast one and he couldn't stop before the end of the runway. The damage was caused as he was still travelling at about 115kph when he got to the end of the runway and crashed into a wall further along.

 

Spokey also spoke about the effect of a tailwind on stopping but let me try and answer the question differently and explain in layman's terms and very simplified, WHY this is so.

 

There is a minimum airspeed for each aircraft below which the wing will stall and stop flying. Lots of things affect the stall speed, but for the purposes of this explanation consider it a constant. The landing speed of an aircraft takes the stall speed and adds a margin to that to ensure the plane flies all the way to the landing.

 

 

Now, if there is zero wind and the plane moves through the air at 100kt, it is also moving over the ground at 100kt.

 

If you are moving through the air at 100kt but you have a tailwind of 30kt you are moving across the ground at 130kt. Lekker when you are cruising: comfortable through the air, but fast to your destination.

 

Conversely, if there is a 30kt headwind, and you maintain a airspeed of 100kt, you are travelling over the ground at only 70kt.  i.e. Fast through the air, but nice and slow over the ground- which is what you want when you are landing.

 

 

Remember,  until it has landed the airplane does not care how fast it is moving over the ground, it is air moving over the wings that stops the wing stalling and keeps the plane aloft. However, once you are on the ground groundspeed becomes crucial as  you want to be as slow as possible because you ultimately need to stop.

 

Stopping a plane travelling at 130kt as opposed to 70kt is obviously a different proposition and therefore a plane typically lands into the wind because in addition to the lift provided by the plane's forward movement through the air,  the wind moves more air over the wing allowing you to remain airborne but land at the lowest groundspeed.

Nice Eddy, thanks! Like your explanation.

[Bonus]

Check out this "short landing". 

 

It was during aircraft testing, so an empty plane being pushed to it's limits - but 14 seconds from touch down to stop is amazing. You can see the plane rock on its suspension as it actually stops.

 

https://www.youtube.com/watch?v=rqSTVWw7twU

[Frosty]

I initially thought it was the a380, but it was a bit early in the morning for it, it usually lands pretty much bang on 7am, so that’s why I decided it wasn’t it.

 

I actually saw it come back in at around 7:15 as I passed the runway.

 

@LWB, don’t know the runway numbers, but the A380 landed on the right hand runway but pretty soon after another airline landed on the left hand runway.

Watch this video, as it explains the markings you see at airports.

 

https://youtu.be/9r4WZNLd8pU

[The Ouzo]

Watch this video, as it explains the markings you see at airports.

 

I'll give it a watch.

But from my vantage point driving/cycling past there is no chance of seeing markings.

[Bateleur1]

I'll give it a watch.

But from my vantage point driving/cycling past there is no chance of seeing markings.

 

Comeon.  Where is youre sense of adventure.  Just hop over the wall and have a quick look. 

[eddy]

Nice Eddy, thanks! Like your explanation.

 

Coming from a pro, I take that as a compliment. It means I at least understood some aspects of "principles of flight" during my SPL days.

[The Ouzo]

Comeon. Where is youre sense of adventure. Just hop over the wall and have a quick look.

Hahahaha

Having been partial to the requirements needed for the perimeter wall whilst I was still working for ACSA, I will not risk it at all.

 

I don’t think they implemented it, but one of the initial requirements was an early warning system that would go off if anyone was within 3m of the wall.

[SwissVan]

Hahahaha

Having been partial to the requirements needed for the perimeter wall whilst I was still working for ACSA, I will not risk it at all.

 

I don’t think they implemented it, but one of the initial requirements was an early warning system that would go off if anyone was within 3m of the wall.

When I was a laatjie we lived in Witkoppie ridge right next to the airport, long before they built the second long runway we used to climb over the fence roughly where runway 03R starts and go play in the forest there... literally would climb on the fence in the corner, lift our bikes over and then ride into the forest

[Bonus]

When I was a laatjie we lived in Witkoppie ridge right next to the airport, long before they built the second long runway we used to climb over the fence roughly where runway 03R starts and go play in the forest there... literally would climb on the fence in the corner, lift our bikes over and then ride into the forest

What a great place to live for any kid! We were in Van Riebeek park way over the other side when we used to ride to the airport.

[SwissVan]

What a great place to live for any kid! We were in Van Riebeek park way over the other side when we used to ride to the airport.

It sure was

[SwissVan]

 

Brave pilot and camera man

 

[Frosty]

I'll give it a watch.

But from my vantage point driving/cycling past there is no chance of seeing markings.

But when someone says runway 03R or 03L or maybe 03C, then you’ll know what they mean, and much more.