Airworthiness Notices - B037, Edition 1 - 4 April 1997

 Installation of Automotive Heaters in Aircraft Engine Compartments

Purpose

The purpose of this notice is to inform the aviation public of the requirements associated with the installations of automotive heaters in aircraft engine compartments.

Background

The installation of automotive type heaters in aircraft engine compartments for the purpose of engine pre-heating has been found useful by many operators in dealing with aircraft exposed to extreme cold weather conditions.

Automotive heaters are not controlled aeronautical products, therefore, it is not the intention of Transport Canada to evaluate and approve such installations as they would normally be regarded as minor modifications. Notwithstanding, the installation of heaters requires certification by an Aircraft Maintenance Engineer (AME) to ensure that such an installation will not adversely effect the airworthiness of the aircraft.

Requirements

Prior to making the required certification, the AME must ensure that:

  • The device is installed in such a way that it will not interfere with any control or the powerplant cooling airflow.
  • The device is installed in such a way that no deterioration of plastic or rubber hoses, cable insulation etc., will occur as a result of the hot air efflux.
  • Provisions are made so that, in the event the heater or any of its parts should become detached, no interference with controls or cooling airflow will result during aircraft operation.
  • The method of attachment conforms to standard aeronautical practices as outlined in manufacturers' manuals or FAA A.C. 43-13-1A, etc.
  • Provisions are made in the aircraft maintenance program to visually inspect, prior to the first flight of each day when the heater has been in use, items located in close proximity to the heater and that could have been affected by prolonged exposure to hot air efflux.

Should it become evident that, through cursory inspections or other means of verification, the installation fails to meet any of the criteria mentioned above, actions must be taken to rectify the deficiency prior to returning the affected aircraft to service.