An air data accessories kit is a crucial portion of any pitot-static testing setup, but it isn't exactly the same as the air data test set itself. This kit's job is to provide you with aircraft-specific connection hardware to let you connect your air data test set to the aircraft.

Each aircraft is different, which means testing requirements and the corresponding accessories will be slightly different each time. In general, a good kit will probably include pitot test adapters, static test adapters, static port blanking units, pre-test probes, hose assemblies, seal kits, spacer kits, lubricating fluid, fittings, a carrying case, and instructions for each item.

The goal with this kit is to give you the right hardware to establish a secure, reliable connection to the aircraft without having to "jerry-rig," a connection. The testing process depends on keeping a clean pressure path. This can't be done if you have a loose adapter, incompatible fitting, damaged seal, or a poorly seated connection.

Start With the Exact Aircraft

The first step in compiling your air data test kit is to understand which aircrafts you're going to be working on. The more specific you can be, the more likely it is that you will succeed with your tests.

This needs to be genuinely specific. Simply knowing you'll be working on an Airbus isn't going to cut it. Each model and configuration has different needs for probes, ports, and testing arrangements. Commercial vs. regional, business vs. military—they're all unique.

Before you put your test kit together, you need to know everything you can about your aircraft. Start with the aircraft manufacturer, model number, model variant, serial number (or serial number range). Next, find out whether it's a civil or military aircraft, a fixed-wing or rotary-wing aircraft, and the RVSM status. You'll also need to identify the pitot tube or probe manufacturer and part number, confirm the static port configuration, and gather any applicable aircraft maintenance manuals and test procedures.

Gathering that exact information helps prevent you from running into common problems, such as assuming one piece will fit two kinds of aircraft. For example, the Nav-Aids ADA320-945 identifies the kit for Airbus A319, A320, and A321 aircraft and tells you the pitot probe models it's designed to work with. This is the kind of information you need to make the most informed decisions. The closer the kit is to the actual aircraft configuration, the less likely you are to run into mismatched parts and procedures.

Match the Kit to the Air Data Test Set

If the aircraft specifications matter, that means the test side of things matters just as much. An air data accessories kit has to connect exactly to the aircraft. The hoses and fittings also need to work with the test set, or your maintenance is not likely to succeed.

Before you order any parts, you need to check your air data test set manufacturer and model, hose requirements, fitting types, fitting sizes, quick-disconnect requirements, pitot and static channel requirements, the number of connections required by the tests you need to run, and you need to know whether simultaneous connections are going to be needed. Even if the kit matches the aircraft, if the accessories within the kit can't work with each other, you won't have much luck.

AvionTEq's Boeing 737 Classic air data accessory kit listing, for example, tells you what pitot and static adapters are included and identifies the kit's AN fittings. Having this information before you buy anything will likely save you a lot of trouble.

The best way to know you're getting the right thing is to verify both portions of the connection by asking this question: Will this fit the aircraft, and will it connect to my test set?

Don't Overlook Pre-Test Probes

Pre-test probes provide an important check before you connect your accessories to the aircraft. This allows you to verify the usefulness of your test setup before actually connecting anything. This is helpful because it simplifies the troubleshooting process immensely.

Here's an example: If your test shows a leak, you now have to investigate not only the aircraft but also the adapter, hose, test set, and seal before you know what the problem is. If you do a pre-test, you can ensure the accessories and test set are working as they should, and then you only have to worry about what's going on inside the aircraft.

Use the Aircraft Maintenance Manual as the Final Authority

Maintenance manuals are the final authority. They tell you how the pitot-static test is performed and what accessories you need to perform it. The order of events should be to begin by figuring out what the manual says is needed, then getting the necessary accessories. It should not be to choose your accessories first, then "make it work." This can lead to bigger problems down the road.

Decide Whether to Buy, Rent, or Replace Components

It isn't necessary to buy a new kit every time a new problem comes along. If you're doing frequent routine testing of the same aircraft or same model of aircraft, owning a test kit makes sense, but for one-offs, it might not be feasible. Still, an aircraft-specific kit protects you from unnecessary trouble, meaning you need to acquire one before moving forward.

Thankfully, there are rental options. Sometimes, borrowing equipment from a distributor is the more practical option. Also, through a trusted distributor, you ought to be able to replace individual components of a kit rather than replace the whole thing. When a seal wears out, that doesn't mean you need to dispose of the entire kit.

At AvionTEq, we buy your old equipment, and we offer rentals, replacement components, and full kit purchases. When it's all said and done, the right air data accessories kit makes testing easier and less complex. If the process seems overwhelming or you're not sure where to start, know that our team at AvionTEq is ready and waiting to help match you with the proper equipment and purchasing options.