87-13-01 BELL HELICOPTER TEXTRON, INC. (BHTI): Amendment 39-5911. Applies to Model 222, 222B, and 222U helicopters (LTS 101 series engines installed) certificated in any category. (Airworthiness Docket No. 87-ASW-23)
Compliance is required as indicated, unless already accomplished.
To detect and prevent a possible impending engine power turbine wheel burst which could result in failure of the adjacent engine, severance of the tail rotor driveshaft, and subsequent loss of the helicopter, accomplish the following:
(a) If the scavenge debris monitor is installed on each engine and is wired to a separate red engine chip light which incorporates a light test feature (as previously required by AD 86-17-12, R1, on Bell 222B and 222U helicopters), accomplish the following before further flight:
(1) Revise the FAA-approved Rotorcraft Flight Manual Emergency/Malfunction Procedures, Section 3, by adding the following red engine chip light warning procedure to Table 3-1 (warning lights):
Eng 1 - Chip (Red)
Shut down affected engine.
or
Land as soon as practical.
Eng 2 - Chip (Red) and add the following warning information:
WARNING
"IN THE EVENT OF FLUCTUATING OR LOSS OF POWER TURBINE (Np) SPEED INDICATION, SHUT DOWN THE AFFECTED ENGINE AS SOON AS POSSIBLE. LAND AS SOON AS PRACTICAL."
(2) Revise the FAA-approved Rotorcraft Flight Manual Normal Procedures - Interior and Prestart Check by adding the following:
Eng 1 - Chip (Red), Eng 2 - Chip (Red)
Activate light test feature and check illumination.
NOTE: The FAA-approved Rotorcraft Flight Manual Emergency/ Malfunction Procedures, Section 3, Table 3-2 (caution lights), Eng 1 - Chip (Amber), Eng 2 - Chip (Amber), does not specify engine shutdown on the basis of the amber chip light alone and should remain unchanged.
(b) If the scavenge debris monitor is not installed or is not separately wired, revise the FAA-approved RotorcraftFlight Manual Emergency/Malfunction Procedures, Section 3, Table 3-2 (caution lights), before further flight, by changing the current engine chip light procedure to read as follows:
Eng 1 - Chip (Amber)
Shut down affected engine.
or
Land as soon as practical.
Eng 2 - Chip (Amber)
And add the following warning information:
WARNING
"IN THE EVENT OF FLUCTUATING OR LOSS OF POWER TURBINE (Np) SPEED INDICATION, SHUT DOWN THE AFFECTED ENGINE AS SOON AS POSSIBLE. LAND AS SOON AS PRACTICAL."
NOTE: The scavenge debris monitor may be installed and wired to a separate red engine chip light so that the less stringent requirements of paragraph (a) of this AD apply provided that the details of the chip light wiring modification are approved by the Manager, Helicopter Certification Branch, Aircraft Certification Division, FAA, Southwest Region, Fort Worth, Texas 76193-0170.
(c) If the scavenge debris monitor is not installed or not separatelywired, replace each amber engine chip segment lens no later than December 31, 1987, with a red engine chip segment lens or by an equivalent red light indication which is suitably identified. Once this has been accomplished, remove the flight manual changes prescribed in paragraph (b) of this AD and add the flight manual changes prescribed in paragraph (a)(1) of this AD.
(d) An alternate method of compliance or adjustment to the compliance time, which provides an equivalent level of safety, may be used when approved by the Manager, Helicopter Certification Branch, Aircraft Certification Division, FAA, Southwest Region, Fort Worth, Texas 76193-0170.
Priority letter 87-13-01 issued June 19, 1987, superceded priority letter AD 86-17-12 R1 and priority letter AD 87-10-04 and was effective upon receipt.
This amendment 39-5911 becomes effective May 27, 1988, as to all persons except those persons to whom it was made immediately effective by priority letter AD No. 87-13-01, issued June 19, 1987, which contained this amendment.