Advisory Circular (AC)

Conditional Use of Rated Take-off Power/Thrust up to 10 Minutes for One-Engine-Inoperative Climb Operation

File No. 5009-6-525 AC No. 525-018
RDIMS No. 528484-V3 Issue No. 01
Issuing Branch Aircraft Certification Effective Date 2004-12-01

1.0 Introduction

1.1 Purpose
1.2 Guidance Applicability
1.3 Description of Changes
1.4 Termination

2.0 References

2.1 Reference Documents
2.2 Cancelled Document

3.0 Background

4.0 Acceptable Means Of Compliance

4.1 Existing Type-Approved Aircraft
4.2 New Aircraft

5.0 Maintenance Manual

6.0 Aeroplane Flight Manual

7.0 Aeroplane Log Book

8.0 Headquarters Contact

1.0 Introduction

1.1 Purpose

The purpose of this Advisory Circular (AC) is to provide guidance material for acceptable means, but not the only means, by which transport category aeroplanes may be approved for use of rated take-off power/thrust up to 10 minutes for one-engine-inoperative (OEI) climb operation.

1.2 Guidance Applicability

This document is applicable to all Transport Canada personnel, delegates and industry.

1.3 Description of Changes

This document, formerly AMA No. 525.1521A, is reissued as an AC. With the exception of minor editorial changes the content is unaltered.

1.4 Termination

This document does not have a terminating action. It will however, be reviewed periodically for suitability of content.

2.0 References

2.1 Reference Documents

It is intended that the following reference materials be used in conjunction with this document:

(a) Chapter 500 of the Airworthiness Manual (AWM) - General Provisions;
 
(b) Chapter 525 of the AWM - Transport Category Aeroplanes; and
 
(c) Chapter 533 of the AWM - Aircraft Engines.

2.2 Cancelled Document

As of the effective date of this document, AMA No. 525.1521A dated 14 July 2000 is cancelled.

3.0 Background

Canadian carriers plan aircraft departures using ICAO obstacle clearance criteria. For normal operations the minimum aircraft performance is based upon OEI conditions with remaining engines at take-off power/thrust for 5 minutes. Allowing engine operations up to 10 minutes at rated take-off power will enable credit to be taken for improved climb performance after 5 minutes, thus enabling operation at higher take-off weights from certain runways and in other cases simplifying departure procedures.

4.0 Acceptable Means Of Compliance

4.1 Existing Type-Approved Aircraft

(a) For aircraft currently type-approved (or type-certificated by a foreign airworthiness authority and accepted by Transport Canada), an application for a supplemental type approval (STA) or one-off modification shall be submitted to the Minister so as to change the Aircraft Limitations/Ratings Section or Aircraft Engine Type Approval (Type Certificate) and invoke corresponding changes in flight and maintenance manuals.
 
If the modification affects more than one aircraft the operator must apply for an STA. The applicant shall also submit an acceptable analytical substantiation for existing or revised procedures for inspection of the engine following the use of take-off power/thrust for periods in excess of 5 minutes.
 
(b) Substantiation should be shown for, but not limited to, the following:
 
(i) The effect on powerplant and accessory cooling.
 
(ii) Justification of special inspection procedures following use of extended time at take-off power/thrust.
 
(c) An applicant may submit alternate proposals for consideration to the Transport Canada. The nature and complexity of such submissions will determine the need for verification by test or service experience of the methods used.

4.2 New Aircraft

For aircraft not currently type-approved in Canada, the applicant should declare his intent to make use of the additional time at rated take-off power/thrust for OEI climb operation. This declaration shall be substantiated by analysis or other test work and reflect the potential approximate doubling of exposure time at take-off.

5.0 Maintenance Manual

For existing aircraft, a review of the substantiating material may indicate the need for special inspections or for a change in the existing inspection procedures. If this is the case accomplishment instruction will be incorporated in the existing instructions for continuing airworthiness.

For new aircraft similar instructions should be available as part of the initial documentation.

6.0 Aeroplane Flight Manual

In general, revisions to the Aeroplane Flight Manual may be required in the:

(a) Limitation section;
 
(b) Procedures for obstacle clearance; and
 
(c) Obstacle clearance performance.

7.0 Aeroplane Log Book

The use of the extended rated take-off power/thrust shall be reported in the aeroplane Log Book at each occurrence for traceability.

8.0 Headquarters Contact

For more information please contact:

Policy Standards Coordinator (AARDH/P)
Phone: (613) 990-3923
Facsimile: (613) 996-9178
E-mail: AARDH-P@tc.gc.ca

Original signed by Maher Khouzam

Maher Khouzam
Chief, Regulatory Standards
Aircraft Certification Branch