This AD Revision cancels CAA-T-AD-1-031/98

GSAC

AIRWORTHINESS DIRECTIVE

released by DIRECTION GENERALE DE L'AVIATION CIVILE

Inspection and/or modifications described below are mandatory. No person may operate a product to which this

Airworthiness Directive applies except in accordance with the requirements of this Airworthiness Directive.

Translation of `Consigne de Navigabilité' ref. : 98-149-038(B)R1

In case of any difficulty, reference should be made to the French original issue.

ATR 72 Aircraft

Electrical system - DC generator (ATA 24)

This revision is issued in order to cancel the Telegraphic AD No. T98-149-038.

This AD had been issued following an event where an ATR lost in flight its No. 1 DC generator, then it lost No. 2 one while resetting the No.1 and then after several minutes it lost the main battery.

The investigations lead after this incident (and also a design revue of the DC electrical system and bench tests) proved that the generator reset did not contribute to the loss of the second generator and have enabled to check the proper segregation of the two DC circuits. Thus there are no longer reason to prohibit the reset of a DC generator which is declare failed and the prescriptions of the aforementioned telegraphic AD are cancelled.

This Revision 1 cancels the original AD 98-149-038 issued only on telegraphic form dated March 20th,1998.

Effective dates:

Original AD : Upon receipt of the telegraphic diffusion from MARCH 20th,1998

Revision 1 : July 25,1998

GSAC

AIRWORTHINESS DIRECTIVE

released by DIRECTION GENERALE DE L'AVIATION CIVILE

Inspection and/or modifications described below are mandatory. No person may operate a product to which this

Airworthiness Directive applies except in accordance with the requirements of this Airworthiness Directive.

Translation of `Consigne de Navigabilité' ref. : 98-148-076(B) R1

In case of any difficulty, reference should be made to the French original issue.

ATR 42 Aircraft

Electrical system - DC generator (ATA 24)

This revision is issued in order to cancel the telegraphic AD No. T98-148-076.

This AD had been issued following an event where an ATR lost in flight its No. 1 DC generator, then it lost No. 2 one while resetting the No.1 and then after several minutes it lost the main battery.

The investigations lead after this incident (and also a design revue of the DC electrical system and bench tests) proved that the generator reset did not contribute to the loss of the second generator and have enabled to check the proper segregation of the two DC circuits. Thus there are no longer reason to prohibit the reset of a DC generator which is declared failed and the prescriptions of the aforementioned telegraphic AD are cancelled.

This Revision 1 cancels the original AD 98-148-076 issued only on telegraphic form on March 20th 1998.

Effective dates:

Original AD : Upon receipt of the telegraphic diffusion from MARCH 20th,1998

Revision 1 : July 25,1998