Locked out of private jet - how do you get in?

Question

Ok I'm not a jet owner, I'm a novel writer. I wanted to get my airplane facts right for the story. Say my character has a mid-size (can go overseas) private jet. Has a door lock on the outside door and cargo bay. The bad guys stole his keys, so now he's locked out. My character is a pilot and is with a friend who is a jet mechanic. If the mechanic has tools, and 24 hrs, would they be able to get in to their jet and fly it?

If so, how would the mechanic go about getting in (while leaving the aircraft in flyable condition)?

Or would the characters need to call a locksmith?

I was thinking pretty high in the sky (I was going to have the mechanic literally unscrew the door and then put it back on) but then I thought I'm probably being unrealistic and I should ask someone who's actually worked with jets.

Answer 1

It depends on the exact model. Bobby pins or any key that physically fits will get you into some, you'll need real picks for others, and some custom jobs may require a police snap gun or a locksmith's services. This doesn't correlate with aircraft price: the larger and more advanced, the less likely it is to have any locks at all. At the high end, jumbo jets have no locks and have a (not so) convenient hatch in the gear well, so you can climb inside even without a ladder.

Mechanical locks, with the exception of the more robust types used on burglary-resistant safes and vaults, offer only very superficial security. Airplanes are protected against professional threats by external access restrictions (fences, hangars, guards). When parked at a small local airport, opportunistic theft is deterred by "security through obscurity": very few people are able to operate one, with model-specific skills are involved, and even fewer could make use of a stolen jet. Unlike car parts, aircraft parts come with paperwork.

The locks used on most aircraft doors are small pin and tumbler cylinder types that can only protect against passers-by. The stock locks on the most popular light planes even use wafer tumblers, which offer no resistance to picking - some light bumping with a key from another lock of the same type will get it open. Quite a few owners have opened plane doors with a wrong key by accident.

If you're not concerned about property damage, as in an emergency situation, no picking skill is required to open the kind of locks you'd find on a private aircraft. A non-matching key or a flat-head screwdriver, jammed into the keyhole and forcefully rotated with a pair of pliers, can break small cylinder locks' pins and allow the lock to open. Larger locks require a bit more effort, but it's all fairly intuitive work of destroying what's in the way of opening the latch.

In non-pressurized aircraft, you can also bypass many locking mechanisms by applying well-directed force, which slightly deforms the door to allow the latch can exit the door frame. In some cases this can be done non-destructively, just by elastic deformation. Pressurized doors fit too tightly for this, but the lock is still a standalone device, not tied into the door's operating and sealing mechanism, so damaging it won't leave the plane inoperable.

24 hours is far more time than would ever be needed. 1 hour is enough time to get a professional locksmith, which, with proof of ownership, can get you into any stock aircraft/boat/car/other vehicle with usually no damage to the lock. Another hour will get you a new set of keys, or a change of locks with new working keys.

The time it takes to get into a locked aircraft, in an emergency situation, should be between 20 seconds and 20 minutes, depending on the plane, the characters' skills and equipment, and their willingness to damage the lock. For a larger jet you'll definitely be going after the lock, not the door.

The only entry-resistant doors in aviation are those separating airliner cockpits from the passenger cabin, with electronic locks and solid locking mechanisms. They're rated against different threat models than UL vault doors, but my best estimate based on their construction and weight would place these doors at around TL-15 level, with about 15 minutes of power tools resistance.

For reference, the highest ratings for safes and vaults are TRTL-120 and TXTL-60, indicating 120 minutes contact time resistance against power tools and torches, or 60 minutes against explosives and small thermal lances. In absence of a security response, 24 hours and a good hardware store can get you into Fort Knox.

Answer 2

The only key lock you might encounter on a corporate jet will be a pin/tumbler lock securing the outside operating handle of the main entry door. You won't find anything exotic unless the owner has gone out of his way to install something. Just about all pin tumber and disc detainer locks can be picked fairly easily with some skill and practice and the right picking tools (an electric picking rake or a snap gun makes it so easy pretty much anyone can do it).

This guy's Youtube channel shows how easy it is to defeat most locks, even the most sophisticated "pick proof ones", EXCEPT for one lock that has defeated him so far, called the Bowley lock.

Beyond that, there will be no internal locks you have to worry about. Just oodles of switches.

Answer 3

Another possible way in would be through the emergency exits. Emergency exits are designed to allow them to be opened from the inside or the outside in case rescue is needed.

Many planes that I fly have a pin that is engaged inside the cabin that is to be used when the jet is parked and removed for flight.

In almost every case, the pin is virtually never installed, even when the aircraft is parked on the ground.

So, our hero could open an emergency exit, close it, and take off assuming the locking pin were not installed.

Answer 4

Here's a very much non-aviation-approved solution which may be attractive in that it allows a McGyverish solution to an aircraft with a more than usually resistant lock design.

If "safely flyable" rather than "certified flyable" is acceptable, then cutting any suitable window along a line say 10mm+ from the edge and gaining access via the hole would in many cases be a possibility.

If there are on site repair services available and able to perform a replacement in a suitable period, use them. If not ...

Such a hole can be repaired "with ease" [tm] by applying a sheet of glass (or indeed any suitable strong sheet material) to the window's inner surface and bonding it in place with a "fast enough" setting silicone rubber or other adhesive. Differential pressure would serve to enhance the bond. Silicone rubber is very adequate for this task and many alternatives would be too.

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Really "just for fun" - make the story interesting.

Could I cut a hole in the windscreen and fix it this way ? !!! :-)

Window pressure from airflow at sea level on a surface at right angles to the flow is not more than
F ~~ 0.6 x A x V^2
A = area m^2, V = velocity m/s, F = newtons
Or, per square meter - F = 0.6 x V^2 newton
At say 100 m/s = 360 kph
P = 6000 N = 6 kPa.
Atmospheric pressure at sea level = 100 kPA. At say 14,000 feet Pa ~= 50 kPa.

I'll not attempt to work through that numerically or to refine the assumptions, but it seems doable. Under some circumstances an external windscreen patch may be preferable.

Noting that the edge bond forces, if inwards, increase with the square of the linear edge size. but bond force increases linearly with edge size.

Suitable juggling of Pinternal and altitude may allow an interior patch a relatively low stress ride.
I'd not consider trying it.
McGyver just might.

Answer 5

Getting into a private jet would be the easy part. Safely taking off in a jet in which you are not familiar is hard. Taking off in a private jet without arousing suspicion would be way harder. Especially if the jet were based at that particular airport. Most private jets are not hangared at airports small enough not to be towered and/or attended.

A fast and capable prop would be more likely.