Door Bomb and Safety Catches

Johnny leaves the airport by taxi, ending up in a disreputable part of town. During his ride we see another video phone call with a different interface, and the first brief appearance of some high tech binoculars. I’ll return to these later, for the moment skipping ahead to the last of the relatively simple and single-use physical gadgets.

Johnny finds the people he is supposed to meet in a deserted building but, as events are not proceeding as planned, he attaches another black box with glowing red status light to the outside of the door as he enters. Although it looks like the motion detector we saw earlier, this is a bomb.

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This is indeed a very bad neighbourhood of Newark. Inside are the same Yakuza from Beijing, who plan to remove Johnny’s head. There is a brief fight, which ends when Johnny uses his watch to detonate the bomb. It isn’t clear whether he pushes or rotates some control, but it is a single quick action. Continue reading

Mangalore Bomb

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Sadly for Zorg, just after he deactivates his bomb, a fallen Mangalore warrior remotely activates his own bomb in Plavalaguna’s suite. The remote control is made from a combination lock. The Mangalore twists the dial to the right numbers, and on reaching the last number, a red LED lights in the center. In the diva’s suite, the box that secretly housed the bomb opens, and the bomb rises like a small metallic ziggurat, accentuated in places with red LEDs. A red, 7-segment countdown timer begins ticking down its final 5 seconds.

Aggression

Mangalores are warlike, as in they really like war. They breathe war. They sleep war. They eat war for breakfast, then poop war, then root around in their couches for war scraps and snack on that. The detonation device isn’t very sophisticated, and that’s just fine by Mangalores. If a Mangalore declared a Design major instead of War in college, they’d have been killed on the spot. This device is perfect for a species that just wants to grab something cheap and convenient, make a few modifications, and get to the boom.

We don’t see a deactivation mechanism. And while you can imagine that a nice safety would be to deactivate if the dial drifted more than, say, 5 clicks from the final activation number, Mangalores wouldn’t have it. They’d “liberate” your mother’s homeland merely for having suggesting it.

If I had to improve it in any way, it’s that it places a burden on memory, and there’s not a lot of indication that Mangalores excel in the thinking skills department, c.f. warlike. Do they have the capacity to memorize a series of numbers in order? And it is easy to recall the series in the middle of a war zone? If not, what would be better? They have their weapons with them nearly at all times, so how about a little glowing, red button on the forestock?

Ha. Joke’s on you, Mangalores. As we know from earlier in the movie, you couldn’t resist pressing it, long before you made it to ocean liners. I think if you’re that warlike and stupid, this would be best for everyone.

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Zorg bomb

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When Zorg believes he has recovered the sacred stones, he affixes a bomb to the door of Plavalaguna’s suite. The bomb is a little larger than a credit card, with a slot at the top for a key card to be dropped in. The front of the bomb houses all the buttons and lights. The bottom and top edges are rounded back.

The interface for the bomb is quite simple. Zorg presses three large, transparent buttons along the top in order from left to right to activate the bomb. These buttons glow bright red during the countdown. Below these buttons, four red LEDs blink in succession counting off quarter seconds. At the bottom of the display a 4-character, 7-segment timer counts down from the time set: 20 minutes. The device audibly ticks off each second as it passes.

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Activation

An (adhesive? magnetic?) backing lets Zorg simply place the bomb on the wall to affix it there. Zorg presses the three large buttons in order from left to right to activate it and start the countdown.

Activation analysis

The bomber is after simple activation, but also wants very much to avoid accidental activation. Pressing the buttons in order might happen accidentally, for example from a tire or foot rolling across it. Better would be to have the activation code something much less likely to happen accidentally, like 1-3-2 or 2-3-1.

There’s also a question of whether a bomber would put giant glowing lights, reflective yellow tape, or an audible tick on the bomb (LEDs, if you didn’t know, don’t come with a ticking sound built in.) Each of these draws attention to the bomb, giving helpless victims time to evacuate, alert the authorities, or inform any explosive ordnance disposal personnel that happen to be wandering by. Yes, Zorg wants the bomb to explode, but only after a certain time, so he can get away. He should affix the bomb in some hidden place and design it with a less attention-getting display to suit his fiendish goals.

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Deactivation

Once Zorg realizes that the box he stole was empty, he returns to the Fhloston Paradise liner to look for the stones. His first task is to deactivate the bomb. To do this he pulls out a keycard, and gingerly holds it above the bomb. His caution and nervousness implies that it has a jostle-sensitive anti-handling sensors, and that if he bumped it, it would go off. Fortunately for him, he manages to slip the card in without jostling the bomb, and sure enough, it stops with five seconds to go.

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Deactivation analysis

The keycard is a mostly-smart deactivation strategy. As we can see, Zorg is quite nervous during the deactivation, and in such high-stress times, it’s better to rely on an object than a stressed villain’s memory for something like a password. The card is thin like a credit card and can fit in a wallet, so it’s easy to carry around. There’s a risk that the card could be misplaced, but the importance of the key will ensure that Zorg will keep track of it. There’s a risk it could be ruined and become useless, but we can presume Zorg made it with tough, ruggedized materials.

The problem with the shape is one of orientation. There are four ways a card can be oriented to a slot, and looking at the card, there is no clear indication of the correct one. The copper circuitry printed on both sides is asymmetrical, so it’s at least possible to tell the current orientation. Perhaps this is the “password” that the system requires, and the random stranger picking it up only has a one in four chance of getting it right.

Fortunately for Zorg, he remembers the correct orientation, and is able to stop the bomb.

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Or, this bomb, anyway.