Demco Air Force One Flat Tow Brake System for RVs w/ Air Brakes - Proportional

1997 GMC Jimmy - Demco Air Force One Flat Tow Brake System for RVs w/ Air Brakes - Proportional

Get safe, smooth braking for your towed car with this truly proportional braking system. Car slows perfectly in sync with your RV. Installs permanently so you can just plug in and go. Low-profile design keeps it out of sight and out of the way.

Features:

• Get the safest and most even braking while flat towing
  • Uses the air pressure from your RV's brake line to apply towed car's brakes at the same time, with the same intensity
  • Applies brakes only when needed: no false braking
• Plug in and go
  • System automatically turns on when you connect your towed car to the RV
  • Low-profile components install permanently and stay tucked out of sight
• Monitor your towed car's braking with LED indicator on car's dash
  • Lights up when the brakes are applied
• Avoid damage from over-braking: reactivates car's vacuum-assisted braking
• Protect your motorhome: system meets FMVSS safety guidelines for RVs with air brakes
• Get everything you need: includes breakaway switch, coiled air hose, and all necessary components
  • Add the wireless Coachlink (SM99945 - sold separately) to conveniently monitor the braking system from the RV cab
• Made in the USA

Specs:

• Application: motorhomes with air brakes
  • Can accommodate air-over-hydraulic brakes with additional 1/4" DOT air line (DM16114 - sold separately)
• Compatible with hybrids and other cars with continuous-power-assist brakes
• Coiled air hose length when fully stretched: 7'
• Breakaway cable length when fully stretched: 7'
• 5-Year warranty

"This is the top system I recommend if you have air brakes. Quality, reliable, tried-and-true. It just always works."

Do I Need a Braking System for Flat Towing?

A braking system is a must when towing a vehicle behind your motorhome. Without it, the weight of the towed car can create a safety hazard, strain your RV's brakes, and affect the warranty of both your car and motorhome. Most states legally require a supplemental braking system, so if you don't use one and you end up in an accident (which is more likely since your RV takes longer to come to a full stop), your insurance and liability headache just doubled. You also won't have any breakaway system; if there's an accidental disconnect, there's nothing to bring your car to a stop.

Pros of a Permanent System

The Air Force One is a permanent braking system, which means that it's a one-and-done. Once it's installed, there's no more setup that you have to do. When you plug in the air jumper and the power cord at the front of your vehicle, the system automatically turns on. Just like that, you're ready to flat tow.

While the components are installed permanently in your RV and towed car, they remain concealed and inconspicuous. None of them will interfere with normal driving, and most of the time they are invisible.

How Does the Demco Air Force One Work?

The Demco Air Force One offers truly proportional braking for the safest and most comfortable flat towing experience. Proportional braking means that when you apply the brakes in your RV, the braking system will engage the brakes of your toad (towed vehicle) at the same time and with the same intensity. Whether it's a gradual slow down to a red light or a sudden stop in an emergency, your toad and RV will brake together.

To achieve this, the Air Force One ties directly into your motorhome's air brakes and uses the same air pressure that results from you pressing the brake pedal in your coach to pull down the brake pedal in your toad. The result is uniform, real-time braking that exactly mirrors your RV.

This is a huge advantage over inertia-based systems, where the braking is triggered by sensing the forward momentum of your toad. While often effective, this method creates the potential for false braking, where something as simple as rough terrain can activate the system when it's not needed. Not only does this make for a rough ride, but it can also prematurely wear down your toad's brakes over time. The Air Force One will only turn on when you need it, so you can avoid any false braking.

To deliver the pressurized air needed to activate your toad's brakes, the coach air connection assembly taps directly into your RV's air brake lines.

A pressure protection valve collects air from your RV's supply air line and stores it in an air reservoir tank so that it's ready to use when you need it. This 1-way check valve ensures that your RV's air lines maintain consistent pressure so that the motorhome's brakes will not be affected by the Air Force One. It meets Federal Motor Vehicle Safety Standard (FMVSS) guidelines requiring that supplemental braking systems use a separate air supply and activation relay valve.

On the other side of the air tank, the service relay valve taps into the coach's metered air line. When you press the brake pedal in your RV, the same pressure that's sent to the brakes is sent to the air connection assembly through the service relay valve. The delivery relay valve then sends the pressurized air to the operating unit via the coiled jumper hose connecting the motorhome and toad.

The main operating unit, mounted under the hood of the toad, receives the air from the coach and sends it to the actuating cylinder that attaches to your vehicle's brake pedal. The cylinder will then pull the pedal down and apply the brakes.

With this system, the brakes are applied in the toad at the same time, with the same amount of pressure as in the motorhome. This is what makes it truly proportional.

Vacuum-Assist Braking Means Natural Braking

When you're driving, your vehicle uses vacuum pressure to create the force needed to bring the car to a stop. On most vehicles, this vacuum-assist function does not work when the engine is off. As a result, a lot of supplemental braking systems have to use an excessive amount of pressure to brake the toad.

The Air Force One, on the other hand, reactivates your car's vacuum-assist function by tying into its vacuum line and using the air pressure from the RV to create the needed vacuum. This way your car will brake evenly and naturally as it's being towed, so there's less risk of damage.

Installing the Air Force One

"In my experience, this has the most user-friendly installation of all the permanent braking systems. The RV side of the install can be tricky though! It's a little intimidating to cut into the air lines."

The Air Force One comes in 3 main pieces: the coach air connection assembly, the operating unit, and the actuating cylinder.

The coach air connection assembly mounts on the underside of your motorhome, wherever you can find an open, secure place for it. You'll connect it to the supply air line and the metered air line on your RV using the included tees. You'll then route an air hose to the quick-connector on the back of your motorhome.

Quick Tip: The coach air connection assembly needs to be mounted in a location where the air lines will not be exposed to direct heat sources or moving parts; in front of the rear axle is often a good location.

The coiled air hose, also called a jumper, runs between the RV and the toad and connects the coach air assembly to the operating unit. You'll plug it into the quick-connects at the same time as you hook up your tow bar.

The operating unit will typically install under your car's hood. It's designed with a low profile so you can easily find somewhere to put it. Once the unit's mounted, you'll connect the air lines and splice the wires to the breakaway switch, which you'll need to install on the front of your toad.

The final piece is the actuating cylinder, the part that actually presses the brake pedal down in your towed car. It will mount permanently to the arm of the brake pedal and anchor to the firewall. Though it is permanent, it will not interfere with everyday driving. In most vehicles, it is tucked up where you can't even see it.

It connects to the operating unit via an air hose you'll need to run through the firewall. In most cases, you can cut a slit in the hood release cable grommet to pass it through. Either way, you shouldn't have to do any drilling to get the air line hooked up.

There are a lot of steps to installing the Air Force One, but the truth is that there is no "easy" braking system. It's just a question of what kind is best for you. The advantage of the Air Force One is that, once it's installed, you shouldn't have to touch it again. You don't have to find a place to store it between trips or set it up each time you tow. You just connect your electrical cord and jumper hose and you'll be ready to go.

Built-In Safety Features

Included with the Air Force One is an LED indicator light for safety and peace of mind. This LED, mounted in the toad (on the dash or on the back of the rearview mirror) and visible in your RV's backup camera, will light up whenever your toad is actively braking. It's a simple way to keep tabs on whether the system is working properly or if something is going wrong.

Most supplemental braking systems have a method of letting you know when they activate, but not all of them are checking if the toad is actually braking. There could be an error that causes the system to activate without actually applying the toad's brakes. Or your brake pedal might be continuously depressed when it shouldn't be. But unless you have a system that's monitoring the pedal, you won't know it until the damage is already done. This indicator, however, connects directly to a reed switch on the actuator so it only lights up when the pedal is depressed.

If there's a strong glare on your toad's windshield, the LED light strip might be hard to see. The wireless Coachlink system (SM99945 - sold separately) is a great solution to this problem; the monitor mounts right on your RV's dashboard so it's directly in view. This is a great add-on for convenience and peace of mind.

The Air Force One also comes with a breakaway system. The breakaway system ensures that your car will come safely to a stop if it accidentally detaches from the RV while you are towing. A switch mounts to the front of the towed vehicle. This switch - which wires to the operating unit - includes a pin that connects to your RV's hitch receiver with a breakaway cable. If the car separates, the cable pulls the pin from the switch, triggering the system. A reserve air supply stored in the operating unit will apply your towed car's brakes. This system also has total coach protection built in: if there is a separation, the motorhome's air supply gets sealed off, so its brakes will continue to function as normal.

What You Need to Flat Tow

Flat towing can be a much more convenient way to take your car RVing with you than using a trailer or a tow dolly. It'll save you storage space both at home and at the campsite, and it takes less time and hassle to hook up.

To flat tow your vehicle, there are 5 basic components you're going to need: a tow bar, a base plate kit, a safety cable set, tow bar wiring, and a flat tow braking system.

The custom-fit base plate installs on the frame of your toad so you can connect the car to your RV with a tow bar. Hook up safety cables between the vehicles to ensure that the toad does not separate from the motorhome if the tow bar becomes detached. Tow bar wiring syncs your vehicle's signal lights with your motorhome's tail lights, as required by law in most states. Finally, the flat tow braking system - also required in most states - activates the brakes in the toad when you hit the brakes in the RV, making for smoother, safer braking, and preventing wear on your motorhome.

9599007 AFO115 Demco SBS (Formerly SMI) Air Force 1 Supplemental Braking System for Motorhomes with Air Brakes - Proportional

Replaces Demco SBS SM99202 and SM99243

DM9599007

Installation Details 

Alternate Instructions