CAPS Retrofit

Every 10 years, the rocket must be replaced and the parachute must be repacked. Starting later this month, we are upgrading the rocket for all CAPS retrofits to be the same electrically actuated system that we use in the new G5 airplanes as I discussed in this blog post.

During the development of the gross weight increase CAPS system, we in parallel designed another rocket that we would use for 2013 SR20's and for retrofitting the fleet of SR20 and SR22's. You can see from the pictures below that the new retrofit rocket (the one in the middle) is both slightly longer and bigger diameter than the existing rocket which provides some additional thrust.
Left to Right: Existing, New Retrofit, 3600lb
Testing of this rocket was done in parallel to the gross weight increase rocket and used the same test plans and procedures as the gross weight increase rocket. The testing included many ground extractions using the existing bucket and parachutes to ensure proper extraction.

In order to utilize this new rocket, some changes will have to be made to the airplane. We are releasing a Service Bulletin that will specify the modifications to be made to the airplane. These changes can be divided into two groups, mechanical and electrical. First lets talk about the mechanical changes.

This new rocket is slightly bigger diameter and length which means that the launch tube it sits in and the shelf it attaches to have to change slightly to accomodate it. The Service Bulletin will drill a new hole in the bulkhead to allow for one new bolt hole location for the new shelf. The SB will also trim some parts of the bucket to allow clearance for wire harnesses and the frangible link. So the physical modifications to the airframe are pretty minor.

Illustration showing rocket installation
The other mechanical parts that have to change are relative to the parachute pack. The canopy remains the same, but because of the bigger diameter of the rocket, we had to use a slightly bigger diameter pickup collar. We also standardized the incremental bridle and the thermal protection for the incremental bridle across all platforms to be the same as the G5. So the pack will arrive for installation with these new parts already installed. There is no change to the canopy, or the bag it is in.


Electrically, we have to hook up the two batteries to the rocket. This starts with a new ignition harness at the rocket. To make the connection to the Battery 2 easier, we ship out a new Batt 2 cover with all the necessary hardware installed. Connecting to Battery 1 is a bit more work as we have to change the type of fuse in the MCU, and add a couple of small harnesses between the Batt 1 and the rocket.
Battery 2 cover illustration

Once all of these electrical mods are completed, there is a detailed electrical check which is identical to the electrical check done on every airplane in production.

These mods, along with the rocket and other hardware changes add about 2 pounds to the airplane.

There will be several different Service Bulletins released over the next few months to cover all the different variations of this installation. For example, the G2 installation will use the new G5 hardware, but has several different variations of harnesses due Avidyne, Perspective, and G3 installation differences. Also there are CAPS Maintenance Manual updates that coincide with the Service Bulletin and also POH updates due to system description changes. So there are a lot of technical publications involved in this as well. http://img.ezinemark.com/imagemanager2/files/30004252/2011/11/E10.jpg