The threat from below isn't just from missiles

Terrorist use of man portable missiles (MANPADS) to shoot down an airliner is a scenario recently touted in a U.S. Department of State fact sheet (see ASW, Oct. 3). However, terrorists have other choices as well. Various terror groups must have taken note of the incidence of wheel-well stowaways being found dead many days later, usually when they either fall out on landing gear extension, or putrefy and start to smell in the landing gear well. Even though most of these stowaways climb into the wheel wells in airports in the Third World, the aircraft can fly many sectors before their presence is detected one way or another (see recent ASW accident and incident tables for examples). It's not unrealistic to imagine a "stowaway" terrorist bent on suicide carrying a device to explode after three or four aneroid triggerings (i.e., on third climb-out), say, between London's Heathrow and Los Angeles International Airport (or vice versa).

An explosion in a wheel well is virtually guaranteed to bring down a fully fueled long-haul airliner over a built-up area with the "bonus" of loss of life on the ground as well.

In our view, insufficient attention has been paid to this threat, as evidenced by the number of dead stowaways found in or dropping from well wells. In fact, this scenario does not require a suicidal terrorist. There are many areas in long-haul aircraft where devices can be hidden, particularly the easily accessible (but rarely inspected) wheel wells. If stowaways are getting access to wheel wells, it stands to reason that stowing a bomb would be straightforward in many areas of the world. We urge airlines to tighten inspection of wheel wells, not just for stowaways but also for explosive devices.

On the DC-10/MD-10 and MD-11 aircraft, there is an avionics access door on the forward bulkhead of the nose wheel bay. Access to this pressurized compartment full of aircraft vitals is fairly easy unless, like one airline has done, security seals are affixed to the outside of these avionics bay doors (which are inspected and signed off on prior to each departure).

Regarding the MANPADS threat, instead of spending a lot of money to buy them up from the people selling them to terrorists, maybe numerous doctored missiles should be released into the market. These missiles would have a self-detonating function built-in, where it cannot be found, for example inside the warhead, together with a non-interference exploder. By this means, a terrorist trying to dismantle the weapon to check for a booby trap finds to his surprise that it explodes anyway. The booby trap, if not found, should cause the missile to explode on launch. The explosion would take out, or at least incapacitate, the launch team. Alternatively, a booby trap charge could be hidden in the propellant. There are many ways it could be done, and with possibly greater effect than equipping airliners with missile defenses.