Why no Helicopters at WTC on 9/11?

Most of the people who died were trapped on the floors above the impact. I’m imagining people going to the roof and grabbing on to the landing struts of the copter,then the helicopter could fly down to the river and hover 10-20 feet over the water and the people jump and then head back up to get more people. Granted, it would take some guts to hold on to the landing struts 2000 feet above the street, but considering the alternative, I think I would’ve tried it. Any reason this would not be feasable?

I’m afraid you’ll get no definitive answer from me. I don’t fly helicopters and am not versed in executing rescue operations from them. However, I remember the smoke coming from the Twin Towers was very heavy at the roof level. Perhaps that (the lack of visibility) could have played a role?

And, now that you mention it, I can’t remember seeing anyone standing on the roof of either Tower prior to their destruction. I wonder if that means the roof access doors/stairwells were locked?

Thermal updrafts.

Hot air rises, and the winds can reach hurricane strength.

No chopper could cope.

There were police helicopters flying above lower Manhattan while the WTC towers were on fire (I’ve seen videotape footage of the collapse taken from one of the helicopters). However, as the previous two posters have said, it was impossible to see the roofs of the towers due to the smoke, and the updrafts from the fire would have made flying near the towers suicidal. Plus, in both of the towers the roof doors were locked. The observation decks did not open until 9:30. No one was able to get out onto the roof.

Were rescue and other kinds of choppers available? I find it hard to believe there were no choppers for rescue work in New York City. Did someone specifically decide not to use choppers? And despite Bosda’s explanation (no disrespect meant to Bosda), I think there’d still be pilots with the gonads to take the risk. After all, we saw quite a number of other examples of heartbreaking and inspiring courage that day. Have choppers successfully been used for other fire rescues?

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I vaguely recall an article in the Wall Street Journal in the last year or so that dealt with precisely this issue.

IIRC, basically, the emergency doors with access to the roof were sealed permanently a matter of months before September 11th. The reasoning was that they presented a safety threat or something (allowing uncontrolled roof access) and were unlikely to ever be useful for helicopter rescues from the rooftop.

Recall, major catastrophic failures of high-rise structures had never been seen before resulting from fire. Before the first tower collapsed, no one in FDNY or anywhere else thought that the towers would collapse. Assumming that this is true, would you want to have to ride 1,000 feet down hanging on to a helicopter strut when you could just walk down six hours later? On September 11th, how long was the time interval between the two towers collapsing?

Thirty minutes?

Consider, additionally, the fact that most helicopters don’t have the suffecient power to pick up dozens of people from roofs, they already have seats for the people they can carry. How can you ensure that this happens in an orderly and safe manner? Recall please the fall of the American Embassy in Saigon in 1976(?).

Finally, I think that this was a moot point. I am less sure of this than anything else, but I believe that in both towers, at least one stairway was maintained in each tower, in spite of the “gutted” appearance from the videos. Hence, the vast majority of the people killed in the towers were killed either in the initial impact or directly related to the fire, not the inability to escape from the building.

If helicopters had indeed been used on September 11th, it is a possibility that the death toll would have proven higher.

Damn, four simulposts.

Actually, all stairwells were destroyed at the floors of impact in the North Tower. In the South Tower, one of the three stairwells, Stairwell A, survived the impact, and was open from top to bottom.

Over 470 people above the floors of impact (78-84) in the South Tower could have safely taken Stairwell A downward, but chose to remain on their floors, or headed in vain up to the roof and waited for the doors to unlock.

Gonads have nothing to do with it - you’re dealing with the laws of physics.

Even without a fire, flying a chopper around tall skyscrapers can be a hazardous undertaking due to the air currents around such buildings.

Fires of that magnitude DO generate huricaine force winds and the air currents become extremely unstable and turbulent. That’s leaving aside the possibility of debris being lofted into the air by updraft, getting sucked into the rotors, and causing possibly fatal damage. Superheated air - remember, the fire reached several thousand degrees - can also interfere with the engine’s efficiency, reducing the payload it can carry.

Cling to a skid 2000 feet above the ground? Yeah, I’d do it - problem is, there’s no way to get a chopper that close to a building burning like those two were.

And if you have panicked folks clambering onto skids and such you will also have weight and balance problems, but that’s moot since you won’t be able to get close enough to get to those folks anyhow.

Maybe Johnny L.A. or one of the other chopper pilots will be along presently to explain all this in more detail.

(Assuming that a helicopter could have picked any people up from the roof) I don’t think a person could hang onto a skid long enough for the helicopter to reach a safe enough altitude to drop from. I have had plenty of experience hanging from the strut of an airplane prior to a skydive. It takes everything you have just to stay there for 60 seconds. Granted, the airspeed of the plane combined with the prop wash make it a slightly different situation from a helicopter, but both times I have jumped from a helicopter I was very surprised just how strong it’s rotor wash actually was. Aside from the logistics mentioned above, I just dont see this as being feasible. I would be interested to hear from a heli pilot just how much time it might take to decend from the top of the tower to the shoreline without creating any g-forces which would dislodge any hangers-on.

I did, the moment I saw the fire and damage my first thought was that the metal girders and beams wouldn´t hold for long; and I grant you, I don`t want to be so right ever again. :frowning:
But still helicopters were never an option.

No cite, but after the second plane hit the networks went to a camera that was on a building or on the ground. I thought I remembered the newsperson saying that all of the air traffic (news choppers) around the buildings had been ordered to land/get away from the towers. I doubt this would have applied to police or rescue helicopters, but it might have kept someone trying to be heroic and land on the top of the buildings.

As others have said the updraft made the possibility of some kind of helicopter rescue impossible.

Even on a good day, imagine trying to land on the roof of the North Tower. One thing you can’t see in that photo are the guy wires strung across the roof to hold up the main television antenna.

According to the series that USA Today ran on 9/11 last year, all non-military flights were ordered to land once the air traffic controllers realized what was going on. The first non-military flight allowed of the ground was a lifeflight helicopter, and the pilot had to get permission from the head of ATC.

The jet crashed into floors 93-98 of the North Tower. More than 947 occupants of floors 101-110 of the North Tower died because of their inability to escape the building.

Bosda and Broomstick have it correct on this one.

Aerospace vehicles operate in the air - obvious, no? Yet since air is mostly invisible people tend to discount how violent the atmosphere can be.

Instead, think of something you are probably more familiar with - a boat. Think of the difference between a calm sea/lake and one that is choppy. A boat churning through choppy water is similar to an airplane/helicopter churning through choppy air. Both are at the mercy of their environment. Now think of something on the scale of The Perfect Storm . That is the scale of air disturbance you are dealing with above the WTC while it is on fire. A helicopter would most likely be unable to even ENTER the vertical column of air above the WTC, much less maintain anything resembling controlled flight. Combine that with the plethora of antennas on the towers, and you have something that is just not doable.

I’m not buying the “updraft” argument. Come on, fire coptors dump water on forest fires from relatively low levels. I’ve seen it… Plus, I’m sure a forest fire generates much more updraft than the wtc fires did.

I’m betting that the orders to stay out of the airspace had a LOT more to do with this than updraft.


OK, I’m going to try to explain this to Zuma in lay terms, since by merely making that statement Zuma tells me he or she is not a pilot.

Weight of the aircraft is a significant factor in how well it rides out turbulent air. The aircraft dumping water on forest fires are MUCH larger and heavier than your average helicoptor, and therefore can handle a somewhat stronger updraft/aircurrent. While helicoptors can and are used for fire fighting sometimes, they tackle smaller burning patches.

I would also like to point out that water tankers used to fight fires DO crash from time to time - for the past couple of years every season seems to see at least one that breaks up while in flight over the fire. The stresses imposed by the air currents they fly through may well be a factor (their age is also probably a factor, but there’s some dispute over just why this has been happening)

There is also a point at which they have to ground the tankers, no matter how large. A crown fire that starts generating its own weather patterns will be allowed to burn - it’s too dangerous to fight by any means.

The “all aircraft land NOW!” order had nothing to do with the lack of rescue by the air. The updraft generated by the burning buildings would have flung any aircraft entering it upward at thousands of feet per minute. From a pilot’s perspective this is not theorectical but an obvious statement, like saying “water flows downhill”.

As Pilot141 states, non-pilots do not normally have an awareness of just how much air currents affect aircraft. Even without fires, when flying over farmfields in the summer I have encountered updrafts that have shoved my airplane upward at a rate of 500 feet per minute. Going over a large pile of burning leaves a 1/2 mile below can give you a noticeable push upward. How much more violent is this force going to be when fueled by a burning skyscraper laced with jet fuel?

And that’s just considering the updraft alone.

Two pilots and a skydiver (who has had first hand experience clinging to helicoptors at altitutde) have stated that a helicoptor rescue was just not possible, regardless of “gonads” or any other heroic trait. I’m sure any other pilot who checks in will say the same. If it makes you feel better, I’ll try to get Johnny to drop by and add his two cents as a chopper pilot.

Hi Broomstick. Just rolled out of bed, and my coffee is decaf.

As you know, I fly helicopters. But I’ve only flown piston-powered two-seaters (Robinson R-22 and Schweizer 300CB). I have flown around the skyscrapers in downtown L.A., but I always kept my distance because of the regulations and because I’ve never had a reason to get closer than allowed. Although there are a lot of buildings with helipads on them, I’ve never landed on one because it is forbidden. I have done “pinnacle landings” (which is what landing on a building is) and “ridge landings” (which is similar).

One thing about pinnacle landings is that your approach is steeper than with a normal landing because of potentially dangerous air currents. One of the Robbos I flew was rented by a guy who attempted a ridge landing. He came in too shallow and was caught in a downdraft on the lee side. He couldn’t get out of it and hit the slope short of the top. He rolled down about 200 meters to the bottom. He was okay, but the helicopter was destroyed. (And it had gone through a $70,000 factory 2,000-hour rebuild just a month before!) Granted, the pilot was low-time, and the helicopter was much less powerful than the jet helicopters most people are used to seeing; but it illustrates that flying in air currents – which Pilot141 points out are invisible – can be dangerous. The smaller the aircraft, the more affected it is by air currents. And helicopters tend to be pretty small.

Visibility has been mentioned as another factor. If you can’t see, you can’t land. There are also the obstructions that Walloon linked to. Landing a helicopter, which probably does not have a great reserve of power, with little or no visibility, on a small patch surrounded by masts and cables, in extremely variable wind conditions would be rather dicey to say the least.

The most often-seen helicopters in our cities are the Bell JetRanger (5 seats), the Bell LongRanger (7 seats) and the Aerospatiale A-star (which I think is a 5-seater). These helicopters are not designed for rescue service. Although many have been used for all sorts of utility work, those are flown by pilots that have been specially trained. For example, when you see a helicopter with a sling, the pilot has been specially trained and has an endorsement for such work. You even need special training and have to maintain documents and manuals if you want to use a helicopter as a camera ship. In any case, the helicopters I mentioned are designed primarily to carry a small number of people. They have “car” doors on them that are hinged in the front instead of “van” doors that slide open, as on the Bell UH-1 or the Sikorsky UH-60. They’re not really suited to rescue work. They can be modified for rescue, but that takes time and you need to have a pilot who is trained for it.

Couldn’t someone have made an effort? There was a local news helicopter pilot who rescued people who were trapped by a flood in Van Nuys, CA several years ago. He was grounded for at least a year because his efforts interfered with official efforts og the LAFD helicopter pilots. We all want to be heroes, but sometimes we get in the way.

As threemae said, no one expected the towers to collapse. They were designed to withstand the impact of an airliner, and they did. There was a lot going on before the fires brought them down, and disaster response needs coordination and time. Before the towers collapsed, rescuers thought they had time.

Back to the roof. As I said, the helicopters common in the city are not designed for rescue work. Assuming you could land you’d need the pilot of course, but you’d also need someone to coordinate the passengers. That only leaves three seats available in a JetRanger. It would take a long time to get people down three at a time. And where would you land them? From what I’ve seen NYC is pretty packed. You’d have to fly them to Central Park or someplace, then climb back up to 2,000 feet. Man, I hated it when my instructor would pull a “throttle chop” when I had to climb back to 2,500 in a little Robbo! In my (limited) experience, helicopters don’t have the power to climb very fast.

Hang from the skids? It’s not likely that a pilot would risk it. First, there are balance issues. Unlike airplanes, weight and balance for helicopters must be figured laterally in addition to longitudinally. You get a couple of people hanging off the skids, and you might not be able to control the ship. As SkyBum said, people probably wouldn’t be able to hold on very long – and they’d have to hang on long enough to get to a landing area.

Take a look at their approaches. The helicopters are flying straignt-and-level and usually don’t have obstructions. The approaches are planned to avoid obstructions, and the pilots have a pre-planned escape route. Also, the buckets can be jettisoned if they need to. So what we’re talking about is a long, stabilized approach in helicopters specifically modified for the mission with pre-planned escape routes in an area where obstructions have been plotted and escape routes provided for, versus an ad-hoc rescue attempt with steep approaches in helicopters designed to just carry passengers in an area where buildings confuse the air mass and there are fewer escape routes.

It’s not impossible that some people could have been rescued by helicopter. But at the time, the towers were not expected to fall. The air currents and lack of visibility and the rooftop obstructions would have made things rather difficult to start, then you’d have to deal with a panicked mob. And then you’d only be able to take three or four at a time. One thing you don’t want to do in a rescue is to make more people to rescue. In this particular situation there was the likely potential to lose aircrews and the people who may have been “rescued” by them, and more casualties on the ground when a helicopter that clipped a cable plummeted on top of them and sprayed Jet-A all over the place.