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9/11 Redux 1

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dik

Structural
Apr 13, 2001
25,821
I was unaware of the effects of the canal shore on the Ever Given. I had never thought that Bernoulli was involved.

I was wondering what the effect of the low altitude and the skyscrapers, in proximity to the flight path, had on the 747s flying into the twin towers. I assume there was an effect; does anyone have an idea of what it is? What level of difficulty was involved in flying the planes into the buildings? Alistair may have a handle on this, as well as others.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
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Nothing, we have a similar effect to the bank effect called ground effect which reduces our drag when we get to a wing span of the ground but that's only when we are parallel to the ground.

It's not something I have ever tried in the SIM. Flying under bridges is done a lot end of session and to be honest it rarely results in a crash.

Have a look at the old checherboard approach in koitac in Hong Kong on YouTube they used to basically fly between skyscrapers landing there
 
Thanks for the reply...

There used to be a hill and a hangar at CFB Rockcliffe... and my dad flew between them and was 'on the carpet' for his actions. That's how he met my mom... she was in the RCAF, too.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
Actually, the two planes that crashed into the World Trade Center towers were both 767's. And the other two flights, the one that flew into the Pentagon and the one that crashed in Shanksville, PA, they were both 757's.

John R. Baker, P.E. (ret)
EX-'Product Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
I'd never heard of Kai Tak airport... must have been a real hoot... an approach with 'real' hazards.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
Sorry John... I thought they were 747s... Just checked...the 767 only carries half the amount of fuel and is smaller. A full tank with the smaller craft is approx 4 10^12 J of energy...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
As for the Hong Kong airport, I've only flown in and out of the new one, but I'd heard stories about the old one. Now, I have been in and out the San Diego airport several times so I have experienced at least some aspect of flying 'between' buildings. Flying into Norfolk, Virginia can be fun as well.

John R. Baker, P.E. (ret)
EX-'Product Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
lofty showing it how it was done.


Its still loaded in most sims. I have flown it a few times.

To be honest the sim dynamics won't be programmed for flying near buildings and apart from landing we don't go near the ground.

Like flying under bridges pre 9/11 people used to fly between the towers end of session in the sim. If you are in an old sim they are still programmed into it, the Jetstream 32 sim in the Netherlands still had it 8 years ago, well it had it in the location drop down list. There was a warning on the sim in flight safety DC not to set it up in the briefing notes some 8 years later after 9/11. They will have practised flying round them multiple times. All the targets at the time were high resolution programmed as standard. Don't have a clue if they are still a presume not now on new sims.

I did my twin piston rating at Naples when one of them was training at the time. Don't remember him apart from he locked the Seminole and the instructor went a bit crazy trying to get keys. Next time I was back across the pond was just after they opened the airspace up again we were meant to be banded from class B airspace around Orlando but after a couple of days there was that little traffic and my Scottish accent I ended up chatting about life with the controller. Third day she announced you have been given a waver by the feds your allowed in. Went through it once and then stayed clear. The whole point of being there was drilling holes in the sky to hour build so taking a short cut didn't really help me. Winter haven, St Augustine, Cedar Key, Winter Haven. And repeat the next day. 10 days later go back to the UK.

I can remember sitting with my theory books open on the table watching it develop with a ticket to go over in 4 weeks time after my last set of ground exams with my commercial and instrument course booked just in shock.
 
I have experienced at least some aspect of flying 'between' buildings.

There's at least one small plane version of that; to land at Hawthorne airport, you follow 120th Street until you're past the northwest corner of the former Northrop Grumman building, and then you had to zig to the left to get to the front of the runway. Used to be, there was a 2nd floor conference room right in that corner of the building where you could clearly hear the planes zigging around the corner of the building. They've since torn down the building, and there are a bunch of homes there now; not sure I'd want to live on the western end of them.

runway_jslrno.png


TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
To be honest I can't see how a single engine piston can safely use that airport and comply with the glide clear rules in the event of engine failure.

I presume they will be saying they can land on the freeway. Good luck with that.

Comes of the heading of not my problem though :D
 
It is not so long ago that someone did land a small plane on the a freeway, managed to get it down in-between the cars, no one got hurt.
But of course it would be better if it never need to happen.

Edit: Actually it seems to happen often ..
[youtube cHNNWCCMYVA]

The Seminole is that a airplane?

/A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
There is a joke about the old Hong Kong airport wherein a pilot, forewarned how short the runway is, uses every skill and nerve in his body to get his plane down and stopped in the short length provided, gives a huge sigh of relief then looks out each side-window and say "but gee it's awful wide".
 
yes its a twin petrol engine aircraft which is relatively cheap to run which is used a lot in flight training. We do a 5 hours course called multi engine piston which gets into multi engine flying. I was again hour building out of Winter Haven because they had a load of old aircraft and used to charge you by the tacho hour which is based on engine load. So during takeoff it would record 1.3 hours for every hour flown and if you went low rpm in cruise you could get it down to 0.65 hours. So I used to fly down to Naples low rpm. Do a lesson in the twin then fly back to Winterhaven. Worked out at 40 bucks an hour logged over 2.5 hours. I would get my 5 hours single engine time in my log book and 1.5 hours twin training. There was a bit of an argument about it all because the FAA instructors thought you could only log what you paid for. Which I did in my FAA log book. UK didn't care what you paid for so it was off chocks to on chocks. I only cared what the UK required. When I dumped my FAA log book in the bucket when I was finished with all the instructors scribbles in it they were about crying. I believe after I left there was huge arguments with the Europeans because the FAA instructors wanted to deface the pilots JAR log books like they used to do with the FAA ones.


yes people do successfully land on freeways but usually they are out of town. In town they usually have loads of wires and bridges going over them.

 
same as Hong Kong airport was the one of Amman (Jordan) till 1982-1983 approx
 
Plenty of airports out there that you have to weave your around various obstacles.

Vargar in the Faroes you have to fly along a 2000ft cliff and find a gap with a water fall and then head over it in a valley then hang a left turn round a corner then land as you roll out

Found a vid of it.


Only thing was that approach was off what's called a cloud break out to sea which had a 1000ft minimum. The Ils approach that had you comin along that valley on the right had something like 1400ft min unless you were local and in a BAe 146 . So quite often you couldn't get in off it. So you would find that water fall and fly over it at about 300ft.
 

How clever... a two stroke aircraft engine. What will they think of next? [pipe]

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
I seen some of the 10 worst airports to land on lists.
I always thought Bilbao, Spain would have been one, but it never is.

[Youtube BiDGyQcGmEo]

There are some that have car roads or train tracks running across the landing path, but that can be handled and when it is, it's not a big problem. [ponder]
Even running the plane out in the sea if the runway ends like that, would probably be less dangerous then flipping the plane over on the runway.
I seem to remember that Isle of Man was one of the top ten, as the runway was on a beach.

/A

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein
 
I understand one of the most useless things is 'runway behind you' from an old pilot I knew...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
yep but we usually use that one for take off

dik said:
How clever... a two stroke aircraft engine

Its a sub 3500kg class of aircraft which you don't need a special qualification to move between makes and models.

SEP single engine piston.
MEP Multi engine piston
SET single engine turbine.
MET Multi engine turbine.


Anything single engine you have to ensure you have a somewhere to dump it if the engine goes.

 
isle of Man isn't on a beach that's Barra in Scotland.

Use to fly regularly into IOM and its nothing special just windy most of the time. only ever landed a SEP in Barra and it was easy enough.

Leeds Braford can be a bit of a roller coaster. It was never intended to be a runway to land on. It was only for departing Lancaster bombers in the second world war. But its at 700ft elevation so if the whole of the north is fog bound that's where everyone goes.
 
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