Homebuilders have used many methods and materials to pass wires and cables through the firewall - SOME OF THEM ARE UNSAFE!
In an accident, the sharp stainless steel firewall can cut wire insulation and short power cables to airframe ground - creating an ignition source in an environment of gasoline, oil, and other flammables.
Fires inside the cowling are particularly bad due to the presence of fuel, oil, and a high volume of forced airflow. As a result, engine fires are often extremely hot, expand rapidly, and quickly melt simple, inappropriate grommets and other "sealing" materials. The idea is to keep the fire and fumes out of the passenger compartment. Simple grommets and bushings are not sufficient.
It's called a FIREWALL for a reason! Don't create breaches using substandard materials!
Firewall Pass-Thru is easy to install in your airplane's firewall and comes with everything you need...including hardware and clear, concise instructions (with images) to insure a proper, successful installation.
(Right) Images shows the Firewall Pass-Thru as viewed from the crew side of the firewall. Notice the nice radius on the spun flange.
(Left) A view from the engine side of the firewall. The reinforcement disc is installed, which covers the jagged hole cut in the firewall and "captures" the firewall between the disc and the spun flange on the passenger side (see image above)
Most builders will utilize TWO Firewall Pass-Thru units:
- One for high current cables (battery, alternator, and Main Buss power) and...
- A second Pass-Thru for small signal wires such as EGT/CHT and other engine instrumentation and control functions.
- Complex aircraft may require a third Pass-Thru for all those "bells and whistles" - or for future "growth".
Firewall Pass-Thru acts in several very important ways:
- REDUCES the chance of fire ignited by electrical current due to crash damage.
- REDUCES the chance of chafing of wires that cross the firewall - Which can START a fire, cause equipment to malfunction or fail.
- SLOWS DOWN PENETRATION of an in flight engine compartment fire - Increasing the pilot's time to get the airplane safely on the ground.
- SEALS FIREWALL penetration points for wiring and cabling - reducing the chance of carbon monoxide, or other toxic fumes to enter the passenger compartment.
View from passenger-side of firewall. Cables are wrapped in firesleeve material and inserted into Firewall Pass-Thru
(Above) Image of Engine-side of Firewall Pass-Thru. Hose clamps secure firesleeve and assembly to Pass-Thru
Additional benefits of the SafeAir1 Firewall Pass-Thru
- Pass-Thru Fitting is installed from aft to fore in the firewall - providing a smooth radius where wires and cables transition the firewall.
- Stainless steel construction resists heat and fire.
- Firesleeve material is the aerospace quality and is the same material used to protect fuel and oil lines in the engine compartment.
- Firesleeve material is "end dipped" to prevent the absorbtion of fluids
- Backing Ring helps block heat, seal out dangerous gases, and keeps the Firewall Pass-Thru intact in the event of an accident.
- Round shape reduces the chance of stress risers.
Available exclusively through AveryTools.com