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Demco Air Force One Supplemental Braking System for Motor Homes with Air Brakes - Proportional

Demco Air Force One Supplemental Braking System for Motor Homes with Air Brakes - Proportional

Item # SM99243
Retail:$2,962.99
Our Price: $1,329.00
You Save: $1,633.99
Tow Bar Braking Systems

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Product Expert Mike S

Is this right for you? Product Expert Mike S says:

Yes, if you:

  • Have a motorhome with air brakes
  • Don’t have time to waste setting up a portable system before every trip
  • Tow a nicer or newer car and want the most precise braking possible

No, if you:

  • Upgrade your towed car every few years
  • Are hesitant to make any modifications to your motorhome
This truly proportional braking system uses the air pressure from your RV's brakes to apply the brakes in your towed car in the same manner. Low-profile design installs out of your way and is always at the ready. Great Prices for the best tow bar braking systems from Demco. Demco Air Force One Supplemental Braking System for Motor Homes with Air Brakes - Proportional part number SM99243 can be ordered online at etrailer.com or call 1-800-496-5010 for expert service.
  • All Info
  • Reviews (238)
  • Q & A (0)
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  • Why etrailer?

Demco Tow Bar Braking Systems - SM99243

  • Brake Systems
  • Air Brakes
  • Proportional System
  • Fixed System
  • Demco
  • One Time Set-Up
  • Power Assist Brake Compatible

This truly proportional braking system uses the air pressure from your RV's brakes to apply the brakes in your towed car in the same manner. Low-profile design installs out of your way and is always at the ready.


Features:

  • Supplemental braking system applies towed vehicle's brakes in proportion to braking action of RV
    • Towed car's brakes are activated at the same time and with the same intensity as those in your motor home
  • Truly proportional system uses the air pressure from your RV's brakes to apply the brake pedal in your car
    • Coiled air hose connects air assembly in RV to operating unit in towed car
  • No false braking
    • Coach air brakes must be activated for system to apply towed car's brakes
  • One-time setup - no need to remove or to activate each time you tow
    • Operating unit and actuating cylinder stay hidden so everything is out of your way when you are driving
      • Low-profile design of operating unit allows for more room in the engine compartment of towed car
      • System automatically functions when towed vehicle is connected to RV
  • LED coach notification system illuminates when the towed vehicle's brakes are applied
    • Connects to towed car's brake light switch to ensure proper reading
  • Vacuum-assisted function of towed car is activated with air from the coach brakes
    • Less force is needed to move the brake pedal in the car, resulting in more natural braking and less risk of damage
    • Compatible with vehicles that have continuous-power-assist brakes
  • Breakaway included
  • System meets FMVSS safety guidelines for motor homes that use air brakes
  • Necessary installation components and an instructional CD included
  • Made in the USA


Specs:

  • Application: motor homes with air brakes
    • Can accommodate air-over-hydraulic brakes - additional 1/4" DOT air line (not included) may be required
  • Coiled air hose length when fully stretched: 7'
  • Breakaway cable length when fully stretched: 7'
  • 5-Year warranty


A supplemental braking system is a must when towing a car or truck behind your RV. Without it, the weight of the towed car can create a safety hazard, strain your RV's brakes, or affect your RV's warranty. Most states require a supplemental braking system.


Automatic, Truly Proportional Braking

Air Force One is a proportional braking system. When you apply the brakes in your motor home, the system will engage your towed car's brakes at the same time and with the same pressure as those in your motor home, creating synchronized braking.


To achieve this proportional braking, Air Force One ties into your coach's air brakes. The patent-pending process uses air pressure from your coach's brakes to depress the brake pedal in your towed car. The result is uniform, real-time braking that mirrors the slowing or stopping action of your coach. Whether you lightly tap the brakes in your RV or apply them hard in a panic situation, your towed car's brake pedal will be applied in the same manner.


Many other proportional systems activate the towed car's brakes based solely on inertia. With this kind of setup, any activity that affects the forward momentum of your towed car - from the coach actually braking, to driving over a pothole - can activate the supplemental braking system and apply your towed car's brakes. This potential for false braking, which can occur simply from driving over uneven terrain, can create a rough ride for you in the RV and can also wear out your towed car's brakes over time. Air Force One is different, though. Because it is tied into your coach's brakes and is not dependent on inertia, this system activates only when you apply the brakes in your RV, so there is no false braking.


Permanent Installation with Concealed Components

Once you install the Air Force One system, it stays concealed and out of your way - both in the RV and in the towed car. Unlike systems that require you to keep the actuating box under the seat or in the trunk of your towed car, Air Force One does not take up valuable storage space inside of your car. And the components that install on your RV all remain hidden beneath the vehicle so that no room is taken up in its interior either. Because the entire system installs permanently, there is no need to constantly set up and remove this system. You never have to worry about where to store a bulky actuator box when you're not towing. And while most of the components do remain on your vehicle and RV at all times, none of them will interfere with normal driving or braking.


Coach Air Connection Assembly

Because Air Force One uses air to activate, it is a natural choice for diesel motor homes that have air brakes. The coach air connection assembly taps into your RV's air brakes and delivers the air necessary to activate the towed car's brakes through the included coiled air hose. The valves on the coach air connection assembly ensure precise airflow.


Pressure Protection Valve

A 1-way check valve collects air from your RV's brake lines so that it can power your towed car's brakes. This pressure protection valve also ensures that your RV's air lines maintain the same amount of pressure so that the braking in your RV is not affected.


Relay Valves

Metered air from the coach's brakes connects to a service relay valve. This relay valve collects air from your RV's brake lines so that it can power your towed car's brakes. When you activate the brakes in your RV, the delivery relay valve releases the appropriate amount of air to the operating unit in your towed car.


The coach air connection assembly is best mounted in a location on the RV where the air lines will not be near direct heat sources or moving parts, such as in front of the rear axle.


Note: Air Force One is designed for motor homes that have air brakes, but it will also work with RVs that have air-over-hydraulic brakes. Additional parts (not included) may be required for installation on RVs with air-over-hydraulic brakes.


Operating Unit

The operating unit, which mounts in your towed car, receives air from the coach air connection assembly. The unit then diverts a matching amount of air through a hose to the actuating cylinder that mounts on your towed car's brake pedal. That air activates the cylinder so that it applies proportionate braking pressure.


The unit goes under the hood of your towed car, so it is out of your way and always ready. Because this system is a universal fit, you can remove it from your towed car and reinstall it in a different car or truck if needed.


Actuating Cylinder

Small Cylinder

The actuating cylinder depresses your towed car's brake pedal upon receiving the air that is delivered from the operating unit. This small cylinder stays mounted on the arm of your towed car's brake pedal at all times and will not interfere with braking while driving.


Actuator on Pedal

Mount this cylinder so that it is perpendicular to the firewall when you depress the brake pedal. A clamp anchors the actuator to the firewall.


To connect the actuating cylinder to the operating unit, you will need to run the included air hose through your towed car's firewall. You can usually create the necessary, small opening without drilling. In most instances, you can cut a slit in the hood release cable grommet. Simply cut the end of the air line at an angle to poke it through the slit.


Coiled Air Hose Connection

Coiled Air Jumper

The coiled air hose, also called a jumper, connects your towed car to your RV by connecting the operating unit to the coach air assembly. When you are ready to hitch up your car and tow it, simply hook up the coiled air hose at the same time as you hook up your tow bar.


Vacuum Pressure Creates Smooth Braking

Normally, when you activate the brakes in your vehicle, a vacuum multiplies the pressure you apply to your brake pedal, creating the force necessary to stop the full weight of the moving car. On most cars and trucks, this vacuum-assist function does not work when the engine is off. As a result, many supplemental braking systems on the market have to use an excessive amount of pressure to effectively depress the towed car's brake pedal.


Air Force One reactivates the vacuum-assist function of your car's brakes when it's being towed, even though the towed car's engine is not running. As a result, the actuating cylinder does not need to apply extreme force to the brake pedal to achieve proper braking. The operating unit ties into your towed car's vacuum line with a tee so that it can use the air pressure from your RV to create the vacuum your car needs to brake gently. As a result, no additional vacuum pump is required to create the vacuum-assist function for your towed car's brake pedal. Air Force One will replenish your towed car's vacuum after each braking event so that you will get smooth, even braking every time.


Built-In Safety Features

AFO Light in Towed Car

Most supplemental braking systems have methods of letting you know you when the system itself is activated, regardless of whether the towed car's brake pedal is depressed. Such setups leave opportunities for false notification. Air Force One's system is different. This system's LED monitor connects to your towed car's brake light switch. When your car's brake light goes on or off, so does the notification light. So you can tell whether your car's brake pedal is depressed.


Air Force One Monitor Install

You can attach the monitor light to the back of the rearview mirror of the towed vehicle . This way you can see the light from your RV's backup camera or rearview mirror.

AFO Breakaway

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 is wired into 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, causing a signal to be sent to the operating unit. A reserve air supply will then apply your towed car's brakes. This system also has "total coach protection" built in. If there is separation, the RV's air supply is sealed off, so its brakes will continue to function as normal.


Air Force One meets Federal Motor Vehicle Safety Standard (FMVSS) guidelines requiring that supplemental braking systems use a separate air supply and activation relay valve.



9599007 AFO115 Demco SBS - (Formerly SMI) Air Force One Supplemental Proportional Braking System

Replaces Demco SBS SM99202 and SM99243

Installation Details SM99243 Installation instructionsAlternate Instructions SM99243 Installation instructions

This Product Fits The Following Vehicles




Customer Satisfaction Score:


Customer Reviews

Demco Air Force One Supplemental Braking System for Motor Homes with Air Brakes - Proportional - SM99243

Average Customer Rating:  4.9 out of 5 stars   (238 Customer Reviews)

This truly proportional braking system uses the air pressure from your RV's brakes to apply the brakes in your towed car in the same manner. Low-profile design installs out of your way and is always at the ready.

by:

I believe the AFO is the best supplemental braking system for air brakes on the market today. Probably the most expensive also. A lot of work to install but a good system that is truly proportional and safe to use with an air brake system.


Comments
We have used our AFO for over 12,000 miles towing a 2018 Chevrolet Colorado. It seems to be working fine but is really hard to know for sure. It is difficult to see the LED light strip in the camera during bright daylight. When I installed the AFO, etrailer was very helpful even returning my call on a Sunday. I also added a plastic stub next to the connectors on both the RV and toad that very conveniently stores the plastic cover when the brakes are not connected so they do not get lost. I tried to contact etrailer with my simple improvement but no one seemed interested.
Bruce P - 12/14/2021


by:
2014 Honda CR-V

AF1 is amazing so far. I did the installation by myself. I have a 2014 Honda CR-V and bought it for towing. Watching the video helped me through it. The car installation portion was pretty straight forward. The video is better than the instructions overall, but I read through the entire instructions before beginning. I was able to install the RV tank without putting the rig on a lift. Depending on how big you are and flexibility, it can be done with the RV on the ground...it just takes longer. Also, I would recommend knowing where you are going to mount your RV tank. I mounted the tank near the rear and didn’t have enough brake tube after doing the car. Picked up an extra 20 ft at Autozone or order the tube with etrailer.

The customer service center is very helpful too. Many thanks to Mariah for the outstanding assistance. Finally, I would say that if you order the brackets to mount the emergency brake away for your car, you may have to cut them down with a grinder. It is so much nicer not putting the brake buddy in the car now. Looking forward to enjoying it on trips. I drove the rig about 20 miles yesterday, and the light came on and I honestly couldn’t tell the car was back there other than looking in the video and seeing the light on the car during braking. Highly recommend this unit.


Comments
5.0 Product is working great! No issues. Minor adjustment to brake cable after a year. It took 5 mins.
Darryl W - 07/28/2021


by:

I installed it myself, followed the eTrailer installation video. I have used it a year, works great, have put over 3000 miles on it. No issues. Struggled with using a portable brake system and decided to do it right. It was the right choice.


Comments
Perfect, way better that the portable device
Jay - 07/23/2022


by:
Ford Ranger

This system has worked great for my flat towing of my Ford Ranger. Had my local dealer install the system for me and have had not one single issue with the operation.


Comments
After one year and more than 10k miles have not had a single problem with the Air Force One braking system on my 2019 Ford Ranger.
Robert - 03/08/2022


by:
2012 Saturn Relay

"Out of sight, out of mind" would be the best description I could offer for the Air Force One supplemental braking system! When properly installed, it's effective as well as quick and easy to hook up. Connect the tow bar, safety cables, safety switch cable, tow plug and air line, you're done! Five minutes at most.

I did add a couple of features to my towing system:

1. Using a relay and the extra wire in the connector to the coach, I installed the LED indicator strip on the dash of the coach; no need to rely on the back-up camera to verify operation of the brake cylinder. Coaches that have a tow connector are usually equipped with a power wire to the cab for electric brakes - this wire is a good way to get the indicator signal to the front of the motorhome.

2. I used the 12 V power connection from the coach to connect a charging wire to the car battery to ensure it would not discharge; I used an auto-resetting breaker with a rating below the glass fuse in the 12 V circuit to prevent a fuse from blowing if the charge current gets to high.

In all, a great investment! I have an article I wrote on the install if anyone is interested.




by:
2016 GMC Canyon

Vehicle 2016 GMC Canyon Diesel.
Installation
of the SMI Air Force One supplementary braking system was not too difficult. The instructions from SMI were good as was the video from etrailer. The only reason that I didn't give it a 5 star is because the air cylinder installation on the brake pedal was complicated by an unusual shape of the brake pedal arm. I eventually found a solution.
Tapping into the truck's vacuum line was a little difficult but the kit included everything I needed to T into the vacuum line and install the check valves.
All in all not a bad installation, this summer we'll see how it holds up.




by:
Jeep Grand Cherokee

I could not find anyone in Georgia that had installed the AF1 on a Jeep Grand Cherokee and eTrailer had several videos of their installs so we drove 700 miles to get it installed by these pros. They did a fantastic job and the system is great! The main unit is in the engine bay and you have to get on your knees to see the connection to the pedal. The Grand Cherokee is heavy but I don't feel any difference when towing and it has no effect on driving the the car. I'd give it and eTrailer 6 stars if I could!




by:
2019 Jeep Wrangler Unlimited

I am missing several components.....good response in getting me what's missing. For example I had 13ft of 1/4 hose instead of 50ft. Missing the led mirror kit and connecting blue hose kits all together. I was mailed a collection of some of the parts - not a kit.




by:

I’ve fitted it to my Jeep Wrangler then taken of and fitted to our new Jeep Grand Cherokee. Works perfectly . I had used our 53ft coach without it and in an emergency stop, was a problem stopping in the rain. Now we have had a couple of fast stops and it works great, would be without it.




by:
2017 Chevrolet Equinox

My installer said it was straight forward to install. I really appreciate not having to disconnect anything in the car and then find a place for it until ready to use again. It is out of sight and always ready to use.

I highly recommend this for your braking system!




by:
Allegro

I ordered an Air Force One breaking system one year ago, for my 2019 Allegro Bus 45OPP, and my 2012 Honda CR-V.
I paid $1080.00 with free shipping from E-Trailer. The unit arrived in perfect condition. I installed the system myself, in about three hours on the Motorhome. I had previously ordered a special hose/ tube cutter. The only part of the installation that was a little intimidating was cutting the correct air lines on the coach, however after viewing the installation video everything was made clear.
The install on the Honda took about two hours, I did have to call the people at E-Trailer , but they cleared up my questions.




by:

Love the fact that I don't have to wrestle with a bulky brake controler




by:

Seems to be working well. Wife and I did our own installation and it was challenging. Standing on my head under the dashboard mounting the breaking air cylinder at the brake was tough but doable. Tapping into the air brake system on our motorhome also challenging but it all appears to do the job. Glad that job is behind us.




by:
2004 Chevrolet Avalanche

Pulled entire length of route 66 and then some. We had absolutely no issues with all of our etrailer equipment. Thanks for all of your help.




by:
Jeep Cherokee

We have towed a car over 150,000 miles behind our motor home. Most of that time we used another system and always had small problems. When we bought our 2021 Jeep Cherokee we wanted to upgrade our breaking system. Our old system was also inconvenient to setup. This system is so easy to use and works great!!




by:

Came with everything I needed to install it. Great quality and works fantastic!




by:

Air force one there’s a very best braking system you can get for your tow car if your motorhome has air brakes. The etrailer did a fantastic job installing the system both on my motorhome and tow vehicle. I would highly recommend Air Force One and etrailer




by:
2017 Jeep Wrangler

Very nice unit, very easy install on a 2017 Jeep wrangler Rubicon Recon and and Great Support eTrailer !! Super Fast Shipping !!!


Comments
The Air Force One unit has been great. Very easy to use and hook-up is a snap.
FJ40 - 01/19/2022


by:

Product works good. No longer have to put the old box between the seat and the brake pedal and hook up to brake petal. So easy to hook up. Be sure your air hose connections are are secure. Unit does not work when one end of air hose is on the ground. I know from experience. Would suggest ordering an additional air hose just in case you need it




by:

We love our Air Force One braking system. The confidence it was done right by etrailer allows us to tow our 4x4 van without worrying about it!




by:

Installation was easy, compact and out of the way. Had a little problem finding controller location due to clearance. Ended up using velcro on top of the fuse box to hold the controller in place.




by:
2014 Jeep Wrangler

Just finished a 10,000 mile trip trailering a 2014 Jeep Wrangler with Air Force One braking system and we are very satisfied with the product. No issues or failures and once installed, it is very easy to use. We can connect and disconnect from the Air Force One and our Blue Ox towing system in 2-3 minutes.


Comments
After a year, we are still happy with the AF One. We had one issue where it didn’t work and it turned out we let a little grime get into the air fitting. Took some time to figure it out but we cleaned with compressed air and the problem went away. Lessen learned it to keep rubber covers on the air fittings when not in use.
Joe T - 05/17/2020


by:
2016 Jeep Wrangler

SMI Air Force One was the choice I made when we outfitted our 2016 Jeep Wrangler Unlimited last year. I can honestly say, without any hesitation,...this was the best choice ever. The installation was very straight forward. I was reluctant to cut my coaches brake lines...but the technicians at SMI were very helpful. I emailed them a picture of the brake lines that I had identified per the instructions, and wrapped a piece of colored electrical tape around the lines to identify them. The SMI techs wrote back within 20 minutes and confirmed that I had correctly chosen the correct air lines for splicing into. The fittings where a breeze to install. The system has performed flawlessly...and it works so well ---- if it weren't for a video camera view on my dash...I wouldn't even know the Jeep was back there.

When I go to hook and unhook the Jeep. I keep my components in a canvas bag. It contains my Safety cables for the tow bar, lighting umbilical, and the two SMI parts...a coiled quick connect air line, and a safety breakaway cable. The other components of the system stay in place...no lugging them around. They are totally out of sight.

If you have a coach with Air Brakes...this, in my opinion, is the best thing going. Proportional braking...directly metered by your coaches signal line. The system is robust...and includes it's own ping tank, and D.O.T. approved metering valve. I feel it's the safest...and best performing braking system built for a towed vehicle PERIOD.




by:

Should have bought this system sooner. I love that it's fully proportional and truly "plug and play." So much easier to use than my old supplemental braking system that sat on the floor of the car and had to be installed/removed at every overnight stop. I installed it myself, which requires an intermediate level of mechanical aptitude. The instructions that came with the kit and DEMCO's tech support were extremely good.




by:

So far have not had time to install but your service is wonderful



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    Image 1 for
  • Installation Video for SMI Air Force One Braking System for MHs with Air Brakes SM99243
    My contact at SMI Manufacturing advised that their Air Force One Supplemental Braking System for Motor Homes with Air Brakes, part # SM99243, will soon again have an enclosed installation video disc. Current production does NOT have the disc enclosed as SMI is in the process of preparing an updated installation video. We do have videos that we produced here at etrailer that show the installation process. I have linked those for you. One shows installation in a pickup, the other in a SUV.
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  • Best Mounting Location for SMI Air Force Braking Controller SM99243 in 2015 Ford F-150 Platinum
    My technical contact at SMI was quite familiar with your installation question that concerns your non-removable front grille. In trucks like your 2015 F-150 Platinum the best location to install the SMI Air Force controller unit is right on top of the plastic cover over the engine intake. This cover can be drilled to allow mounting of the controller and then be re-installed.
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  • Compatibility of SMI Manufacturing Air Force One Supplemental Braking System with 2004 Jeep Liberty
    According to SMI Manufacturing, their # SM99243 Air Force One is compatible will any vehicle, which means it'll work just fine on your 2004 Jeep Liberty. I've linked you to some flat towing help articles you might find helpful.
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  • What are the Measurements of the Box Part of the Air Force One Braking System
    The SMI Air Force One models we have in stock, # SM99243, are indeed the new AFO115 models and not the old, larger AFO108 models. The overall length is 10-1/2 inches from handle to handle but the actual box part is 8-1/2 inches. It is 5-3/8 inches wide and 1-1/4 inches tall.
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  • Air Force One Supplemental Braking System Actuates Vehicle Brakes When Not Attached to RV
    I spoke with my contact at SMI, the manufacturer of the Air Force One braking system. He had a few possibilities that he recommended you have checked. Where the cable that joins the actuator cylinder on the brake pedal, make sure that there's about 1/4 to 1/2 an inch of slack in the cable. Also, if the vehicle has adjustable pedals, make sure that the pedals are move as close to the seat as they'll go when the tension on the cable is set. This procedure is outlined in Step 7 of the installation...
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  • Installing SMI Air Force One Supplemental Braking System on 40 Foot Dutchcraft on Spartan Chassis
    When installing the SMI Air Force One Supplemental Braking System For Motor Homes with Air Brakes # SM99243 you will need to find the supply air line and the metered air line. On the Dutchcraft motor home on the Spartan Chassis the larger 5/8 inch line is the supply air line, and the smaller 3/8 inch line below the supply air line is the metered air line. I have attached a photo showing witch line is the supply and which line is the metered.
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  • Supplemental Braking Recommendation for Flat Towing a 2016 Ford F-150
    Our installers here do not like the Blue Ox Autostops that you referenced much at all. They don't seem to apply enough braking power and the install is somewhat difficult. Since your Newmar Essex has air brakes the best system for you is the Air Force One # SM99243. It prevents false braking on the F-150 because it doesn't use the coach's brake lights for activation like a lot of other systems do.
    view full answer...


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