Ramp(ant) Paranoia

With terrorists lurking behind every tree, security devices may become mandatory. Prop and throttle locks are top choices.

The general publics cry for security at general aviation airports has caused most of us in the aviation industry to roll our eyes. However, its also spurred some government agencies to look at tightening security or even requiring beefed up security for small airplanes.

There may be a hidden benefit in this hysteria. From an airplane owners standpoint, the real risk from theft is that you’ll discover a gaping hole where your avionics stack used to be. So maybe it makes sense to think about security. And given public paranoia, several aviation authorities have been deliberating what kinds of measures to put into place to make sure light aircraft don’t become terrorist weapons. don’t be surprised if your airport requires you to secure your aircraft in some way.

In 2000 and 2001, a total of 26 airplanes were stolen. For decades, thefts of general aviation airplanes have hovered at an average of between one and two a month-hardly an epidemic. Most of the thefts have been in California or the Southwest, presumably to be used in drug smuggling.

There are a number of approaches to securing an airplane, and we remain convinced the best way is with a locked hangar door. However, most owners don’t have that luxury, especially when traveling.

Whats Out There
There are basically three categories of locks available for light aircraft, so you can choose your poison. For the sake of this analysis, we left out expensive, intrusive actions such as alarm systems, modifications to the electrical system, custom-made metal panels that cover the instruments and beefy cabin door locks. we’ll look at those later.

So youre left asking whether you want to lock your wheels, your props or your controls. you’ll have your own ideas about the potential of each method with respect to theft deterrence, ease of use and potential for damaging the airplane.

Wheel locks have the advantage of being obvious to a would-be thief, possibly deterring the theft. If the airplane cant be taxied, takeoff is impossible. Wheel locks have been used on automobiles, boat trailers and construction equipment for years. Fans of wheel locks point out that a thief trying to steal a booted airplane would have to defeat the device in full view of any passers-by. Cutting tools, lock-freezing spray and removing the wheel would be conspicuous. But wheel locks only work on some airplanes. Forget about locking anything with wheel pants, because the wheel locks need to pinch onto the hub.

They work great on the nosewheel of a twin because you can get to the wheel without crawling underneath the wing and youre out of any propeller arc. However, theyre also the bulkiest devices we tested. We tried two, the Alpha Lock and the Pit Bull Tire Lock.

The Alpha Lock is available from a wide range of hardware stores, auto parts stores and other general retailers, mainly as a device to protect cars, trailers and construction equipment. Construction quality is top-notch, and the vinyl-coated jaws wont mar the rims.

It fits around tires up to 11 inches wide. The unit is made of hardened steel and the lock is said to be impervious to freezing with Freon and resistant to drilling. We found it easy to put the unit on and lock it in place. Although its a two-handed affair, the handle on the Alpha Lock made it easier than its competition.

Best of all, the Alpha Lock is priced like an automotive product rather than an aircraft product. At $90, the Alpha Lock is a clear winner if you decide a landing gear lock is the right option for you.

We also tested the Pit Bull Tire Lock and came away less than impressed. The construction quality was nearly comparable to the Alpha Lock, with heavy-duty aluminum alloy and a quality lock, but the design of the Pit Bull was, well, clunky, in our view.

It takes two hands to position the two calipers and then with your third hand you slide the lock into place. After a few tries, we managed to get it locked, but we cant see this becoming a simple affair.

In addition, to install the cylindrical lock, you need to slide it into the appropriate set of holes, which are drilled into each piece of the lock. Deciding which one lines up best takes some fumbling in the daylight; we cant imagine doing it at night in the rain.

Speaking of rain, the holes are machined into the cast aluminum and do not have drains on the bottom. Anyone else spot a potential for gunk buildup and corrosion? A weather cover is available for another $8, but it seems like it should be standard equipment.

The heavy-duty polyolefin-coated tips on the calipers, there to prevent marring the wheel, had a made in the back yard appearance, although they worked fine. The Pit Bull is adjustable over a wide range and would fit a much larger tire than the Alpha Lock, but we don’t see that as being much of an issue among light airplanes, except perhaps those with really big tundra tires.

Finally, the most off-putting thing about the Pit Bull is its price-$350. While the Pit Bull works as advertised, wed pick the Alpha Lock even if price were irrelevant.

Prop Locks
Hanging a chain on the prop is a time-honored security device. For this, you don’t really need an aircraft part. Shopping locally at a motorcycle shop or even a high-end bike store will yield several options for high-quality chains and locks.

Prop locks have the advantage of being simple, portable and conspicuous. However, because theyre not specialized parts, some owners decide to save a few bucks and buy a lightweight bicycle chain and a drug store padlock.

We hesitate to be too critical because, as we said at the beginning, airplane theft isn’t the dire threat some people believe it is. Even so, if youre going to do something, do it right. A flimsy cable or chain offers little obstruction to a bolt cutter and would allow a thief to cut through it in the blink of an eye.

We tried a prop lock offered by Sportys Pilot Shop for $170. At six feet long and 12 pounds, this vinyl-sleeved chain/lock is a serious security device. The chain was long enough to allow it to be slung around each blade and crossed over the spinner without any of the unprotected parts banging on the airplane. Although we didnt subject it to destructive testing, we came away convinced this is not your kids bike lock. Its of high quality. There are a few things wed like to see changed, however. The black vinyl sleeve would be better in red or orange, given the proclivity pilots have for sketchy preflight inspections. Start the engine with this baby attached and youd better be pre-approved for a second mortgage.

In addition, the key is required to lock the chain, rather than just to unlock. While we can appreciate the lock design that makes this an advantage, we also found that locking this chain could be a handful if not placed just so on the prop. But we think a little practice would make this a non-issue.

In addition to the chain locks, we tried the Pit Bull Puppy Prop Lock and the Prop Club. Design and construction of the Pit Bull Puppy were similar to the Pit Bull Tire Lock, although the unit was about half the size.

The design seemed a little more elegant as a prop lock than as a tire lock, but again, we found problems that make this lock unsuitable for most general aviation airplanes.

The biggest problem we ran into is that the Puppy doesnt stay secure on the blades. The unit apparently was designed with turboprops in mind. We tried it on a variety of singles and light twins, two bladed and three bladed, fixed and constant speed, and found that in every case, you could slide the lock off the end of the prop without unlocking it.

But thats not all. The painted metal device had almost no provision for protecting the propeller blade. The inside of each caliper had a thin strip of rubber-like tape that felt like it would peel off with little persuasion. Even with the strip in place, the caliper was free to scrape along the blade unless the lock was carefully handled. In addition, the ends of the calipers can clunk into the cowling.

We would call the Pit Bull Puppy a non-contender for most light airplanes under almost any circumstances. Tack on the $350 price tag, and our enthusiasm withers further. While it may make sense for a King Air or other airplane with fat prop blades, buyers will still need to concoct some kind of protective coating for the calipers. For the price, we don’t think buyers shouldnt have to resort to such measures.

The Prop Club, on the other hand, is a marvelously designed product that encircles one prop blade without posing a risk to the cowling. Its also unique among the products tested in that it has a combination lock and comes with a remove before flight banner. The plastic-coated lock is made of tempered steel with a patented locking system. Plus, when unlocked, it stays in one piece.

The Prop Club is advertised by Winner Aviation as adaptable to a variety of constant speed propellers and of the aircraft we tried it on, it fit them all. Priced at $250, the Prop Club is a pricey but smartly designed (and compact) propeller lock.

Control Locks
Control locks have some real advantages. Theyre out of the weather, so corrosion and ramp debris arent issues in fouling the locks. They typically prevent the airplane from being operated rather than ruining something if a thoughtless pilot forgets to take the lock off. On the other hand, they have some disadvantages as well. A thief might bust into the airplane without noticing its protected, which means fixing a jimmied door or broken door lock.

In addition, a thief who enters the airplane can work to defeat the security lock in relative seclusion. We tried two different kinds of control locks. One covers either the throttle or mixture control. The other locks the yoke and rudder pedals.

The throttle/mixture lock comes in a couple of flavors, one for vernier controls and one for non-vernier controls. These locks don’t fit airplanes with throttle quadrants, which means Cherokee-derived Pipers and most twins, among others.

Although tailored and sold for vernier and non-vernier controls, the designation doesnt necessarily apply to all aircraft. For example, we found the vernier lock fit the non-vernier mixture knobs of a Super Cub and a Citabria, but the non-vernier lock did not.

Each lock is a heavy steel barrel that fits over the knob, with a specialized lock that fits into a slot cut in the barrel and wraps around the shaft of the knob. The difference between the two types of locks is in the position of the slot. The slot on the vernier lock is closer to the panel end to allow room for the button at the end of the knob to fit inside the barrel of the lock.

We tried both locks on a Skyhawk equipped with a non-vernier throttle and a vernier mixture. The non-vernier lock would not fit the mixture knob, but the vernier lock fit both. The vernier lock allowed some play in the throttle, but not enough to start the engine. The locks are made by J-K Products Co. and sold through Sportys for $70.

We also tried the York Gust Lock, figuring that it would be a great benefit to add gust protection on the control surfaces to the equation. The Gust Lock is sold as such, with security something of an afterthought. It doesnt come with a lock, and to add one requires fitting the device to the airplane and then drilling a hole in the Gust Lock for the padlock to fit in.

While simple in concept, the execution comes up a little short, in our view. The Gust Lock fits firmly on the controls and immobilizes the ailerons, elevators and rudder pedals nicely. But asking more of it, frankly, puts it out of its element.

The metal bar that extends from the yoke to the pedals is not robust enough to consider the $130 Gust Lock to be an adequate security device, in our view. Furthermore, we fit it to a Skyhawk and determined it would be fairly easy to just yank the thing off the rudder pedals without even removing the lock.

As we said at the outset, the quest for an airplane security device requires the owner to make some assumptions about how real the threat is and then tailor the response to the type of airplane. Clearly, securing a corporate jet requires a different approach than a flight schools 172.

We also wish the manufacturers would address the problem of pilots forgetting the things are installed. Judging from the number of accidents caused when pilots leave pitot covers or factory gust locks in place, this is, sadly, an area of concern. Wed suggest prop and wheel locks be augmented with a remove before flight banner. Yorks Gust Lock comes with a key fob that boldly reminds the pilot and a window sticker saying the airplane is so equipped. We wish others would follow suit.

Owners of airplanes with more than one door might want to see a warning sticker for each door as we’ll as something like the hangtag Alpha Lock supplies to hang on the yoke. For fixed-pitch applications, a good quality prop lock such as those offered by Sportys or available at motorcycle shops probably offers the best combination of security and convenience, although were still somewhat reluctant to encourage people to hang 12-pound chunks of metal on their props. If you have a constant speed prop, the Prop Club deserves a serious look. Owners of retracts should consider the Alpha Tire Lock, which, in our view, is an elegant and cost-effective product. Incidentally, we also found the Alpha fits even small tailwheels, which typically arent faired, but we don’t recommend that application because it may be possible to take off while merely dragging the lock along.

We also admire the simplicity of a throttle/mixture lock, and would be more enthusiastic in our endorsement if they came with warning stickers advising the bad guys not to bother breaking into the airplane.

The bottom line is that if you believe the threat of your airplane being stolen is real, a prop lock or wheel lock is in order. However, if you don’t, we suggest a throttle/mixture lock – if one fits your airplane – because it poses the least danger of inadvertent damage to the airplane.

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by Ken Ibold

Ken Ibold keeps his Citabria in a locked hangar in Orlando. Hes editor of Aviation Safety magazine.