Good News, Really
What is the barbarian fascination with airplanes?
Bill Gertz reports that terrorists have smuggled Russian SA-7 anti-aircraft missiles into the US. So now they want to shoot us down. Lovely.
The SA-7 is the Soviet/Russian version of the Stinger. It’s portable and shoulder launched — and therefore not much threat to a civilian jet.
The range of the thing is only three miles, but — and this is the first key — it’s only good to an altitude of about 13,500 feet. In other words, a terrorist is going to have to hit a plane either immediately after take-off or immediately before landing. And it’s certainly easier for us to secure the area around our airports than it is to secure every last air route.
The second key is the size of the warhead — or lack thereof. Man-portable rockets have a very small warhead. They’re good at shooting down helicopters, which have only one rotary wing to keep them aloft, or small fighters, which are little more than unstable flying fuel tanks. Shrapnel goes in, fuel goes out, fire ensues, plane goes down.
But it’s not that simple to take down a 737.
Civilian planes not only fly more slowly, they also fly with more stability. An F-16 can turn on a dime, mostly because its airframe is inherently unstable. Think Newton and you’ll understand why. A Boeing civilian jet steers like a house; it even takes forever and a day just to change altitude. Its design is inherently stable, so it takes more effort to move the thing.
So, let’s pretend an SA-7 hits on of a 747′s four engines. There’s a small fire, fuel loss, and a loss of power. But wait, the plane is only at 8,000 feet, and even with a missing engine, that’s not going to change any time soon. The pilot will, in all probability, still have plenty of time to turn the beast around and get it landed.
Now, perhaps several terrorists with several missiles could all take aim at a single aircraft. They sure could, and the results would probably be quite deadly. But now there’s a large, well-planned, and organized conspiracy. And those are a lot easier to detect than a single man with a missile in the back of his Town & Country.
If this is the sort of desperation plan the barbarians are reduced to, then we’re already winning.
Stephen -
I hope you are right, as I’ve been worried about this threat since September. But question for the class: what affect would a SA-7 have on the wing itself?
‘Cause I’m with you when you point out that modern airliners can do without an engine (or two, or three — pretty much as long as they have one I think they’re ok).
But they don’t do so well with just one wing.
What’s the fascination with planes?
o Flight is a symbol of power and achievement.
o They’re fragile; a little damage leads to a catastrophy.
o Airlines carry a lot of people.
o They can’t shoot back.
Even though the SA-7 only carries a 1.1kg warhead (according to my 1990 copy of World Naval Weapon Systems), the danger would be that a detonation near an engine would cause damage to the fuel and hydraulic systems along with the engine. If the shutoff or fuel tank (remember the bulk of fuel is stored in the wings, and I don’t believe that civil aircraft have self-sealing tanks. I may be wrong.) vent valves are damaged, the crew might not be able to contain a leak or fire. If the hydraulic systems bleed out, the aircraft may become uncontrollable.
They may not have to be near an airplane to use it as a bomb.
I have to disagree. Fuel is pretty explosive stuff and hot shrapnel can ignite that. Furhermore, if it’s a big slow target, just launch more than one missile at it. A terrorist wouldn’t have to be that close to the airport.
In Tampa we see commercial and military jets cruising around all the time, a lot closer than 13,000 feet. Put a dozen stingers in a van get a few blocks away from the airport and pick a few targets. Sure, it’s all still fantasy at this point, but don’t underestimate the damage. Just one shoot down and the industry comes to a halt again.
Just to add to the previous comments, while you’re right that a 747 wouldn’t have any problem flying with one engine taken out, what about a plane that only has 2 engines? I think they’re designed to be able to fly with one engine out of commission, but I think if you hit an engine while the plane was trying to take off, it probably wouldn’t be able to recover. Same thing for an airplane on a final approach.
You’re both right and wrong, Stephen. You’re discounting the golden bb theory here. In theory, a warhead detonation behind an engine could send shrapnel through the wing tanks and cut hydraulic lines. You’re now experiencing a loss of pressure in 1, perhaps 2, and rarely in all 3 hydraulic systems – you’re also venting gasoline, your aerodynamics might be shot, oh and you’ve got a working fire on board (assuming that the fuel tanks didn’t fire off in series down the line turning you into an aluminum shower.) The potential is there for things to start going wrong a lot faster than the flight deck can keep up and/or prioritize them.
And it CAN happen. When the number 2 engine on United flight 232 blew itself to pieces, it opened the system on all 3 hydraulic systems. When the pilot radioed United to get the engineers working on how to get the plane back on the ground, they told him it was impossible to take out all three systems – there was no plan. They were lucky to have an experienced flight crew and a training pilot with his family in the back who came up to assist.
But you are correct that a larger-scale, multiple missile go is going to raise a lot more flags at the planning stages.
Two Words: Marine One.
That’s the helocopter equivilent of Air Force One, which I’d bet we won’t be as seeing much of anymore.
As it turns out, this latest warning was based on the discovery of a used missile tube near a US base in Saudi Arabia. The bad guys might well have missiles here, but there’s not really any added evidence of that now.
Military aircraft are also designed to take damage, which civilian airliners aren’t.
If a missile hit the engine and didn’t damage anything else, the airplane will probably fly okay. And engines have shear pins that cause them to depart the airplane under high stress.
But that’s a big IF. The wing of a jet is basically a large fuel tank. A good-sized explosion that ruptures the fuel tanks in the wing WILL bring the plane down. In addition, there are tons of control surfaces and actuators in the wing. Modern jet wings are just full of contraptions like leading edge slats, spoilers, flaps, and ailerons. Cause a slat to deploy on one side and not the other, and the plane is uncontrollable.
I’m not as worried about hydraulic damage – the Sioux-City jet (flight 232) lost its hydraulics due to a design flaw in the L-1011 which routed all the hydraulic lines together near the engine. Other aircraft don’t have that flaw. Hydraulic systems have emergency cutoff valves and redundant paths through the airplane.
All I know is, I don’t want to be on a large jet that takes a hit from a shoulder-fired missile.
One nitpick – the F-16 is not dynamically unstable. The foward-swept variant was, but it was an experimental prototype that came much later. Dynamically unstable planes are impossible to fly without computer guidance, and the F-16 was designed long before they had computers capable of the doing the job.
Modern jets like the F-22 are either dynamically unstable or have neutral stability for manoeverability and fuel efficiency.
Dan
Wrong, Steve.
A commercial airliner hit by a stinger or sa7 is probably going down. Commercial aircraft fly well below 13,500 feet many miles from the airport they are leaving or arriving at. Point is, these missiles have been around and unaccounted for for a decade or more. Why the panic now?
Alternatively, try it this way: An airliner is a big, damage-resistant target, but there are times in its normal operation cycle where it is more than normally vulnerable. If your 747-XL is in normal cruising flight, losing one engine and a batch of other stuff might not be as much of a problem. How’s about when it’s on final descent to contact, maybe about 100 meters off the runway and committed to land? Or fully loaded and taking off, all four engines at full civilian power, the tail just fifty feet from the tarmac? What do you think would happen if you put your SA-7 into her then?
Timing’s everything, man.