Aircraft
Certification Service Washington, DC U.S. Department of Transportation Federal Aviation Administration
CE-10-19 R1
March 17, 2010
This is information only. Recommendations
aren’t mandatory.
Introduction
This Special Airworthiness Information Bulletin (SAIB) advises the
owners and operators of general aviation (GA) aircraft of an
airworthiness concern, specifically the need to inspect properly and
maintain the exhaust system to prevent carbon monoxide leakage into the
cabin and to install a commercially available carbon monoxide detector
in the cabin. This revision adds the Federal Aviation Administration
(FAA) Technical Center library website and revises the recommendation
section.
At this time, this airworthiness concern is not considered an unsafe
condition that would warrant an airworthiness directive action under
Title 14 of the Code of Federal Regulations (14 CFR), part 39.
Background
This SAIB is in response to a National Transportation Safety Board
(NTSB) investigation of an accident on December 17, 2000, where a Beech
Model BE-23 aircraft impacted terrain killing the commercial-rated
pilot, the sole occupant of the airplane. The NTSB determined the
probable cause of the accident was in part “the pilot’s incapacitation
due to carbon monoxide (CO) and a fractured muffler.”
The FAA tasked Wichita State University to conduct research that
focuses on carbon monoxide safety issues as they apply to general
aviation products. A technical report titled “Detection and prevention
of carbon monoxide exposure in General Aviation Aircraft, Document No.
DOT/FAA/AR-09/49, dated October 2009” was published, and is available
from the National Technical Information Services using the contact
information noted below, and is also available electronically at
http://www.tc.faa.gov/its/worldpac/techrpt/ar0949.pdf. The report shows
that 43 commercially available CO detectors, sampled from each of the
five sensor technology types (biometric, electrochemical, spot,
infrared, and semiconductor) were surveyed to determine the most
appropriate sensor technology. The electrochemical sensor-based CO
detectors were found to be most suitable for use in the GA environment.
Limited field testing using portable electrochemical CO detectors was
conducted in two GA aircraft models to determine the best location for
a CO detector. Based on the analyses of collected CO data, the
instrument panel appeared to be the best location for the placement of
CO detectors. The report notes that, to increase the probability of
being able to detect at least 50 parts per million (PPM) anywhere in
the cabin, the CO detector should be set at a lower alarm threshold of
35 PPM. Performance parameters and specifications of various CO
detectors (available on the market) were compiled into a database as
shown in Tables B-2 through B-5 of the technical report.
Recommendation
The FAA recommends that you do the following:
Consider the information in the technical report, and use a CO detector while operating your aircraft.
To detect leakage of gases
into the cabin due to cracks in the exhaust system, conduct engine run
up tests with cabin heat on and check for CO in the cabin with a
hand-held CO detector during 100 hour and annual inspections.
Continue to inspect the
complete engine exhaust system during 100 hour/annual inspections and
at inspection intervals recommended by the aircraft and engine
manufacturers in accordance with their applicable maintenance manual
instructions.