6139523298 

1+1 Transport 

Canada 

Ottawa, Ontario 

KIAON8 

August 01, 2013 

Docket Operations 

Transports 

Canada 

M-30, U.S. Department of Transportation (DOT) 

1200 New Jersey A venue SE 

Room W12-140 

West Building Ground Floor 

Washington, DC 

20590-0001 

Attn: Eric Haight 

13:50:43 08-02-2013 

Your file Votre reference 

Docket No. FAA-2013-0502 

Our file Notre reference 

RDIM:S # 8634739 

Subject: FAA Special Conditions: Eurocopter France, EC175B; Use of 30-Minute Power 

Rating 

Dear Mr. Haight, 

By means ofSpecial Conditions (SC) No. 29-030-SC the FAA proposes three (3) requirements 

for the EC 175B helicopter to use the "30-minutes power rating" that was certificated on the 

PT6C-67E engine (refer to FAA 33-010-SC). This new engine power rating is more than the 

rated maximum continuous power but no more than the rated take-off power. This new rating 

allows the EC175B helicopter Hovering out of Ground Effect (HOGE) in hot and high ambient 

conditions to hover for more than 5 minutes. 

Over the years, Several Special Condition have been issued by FAA for the same feature and 

they provide minimum certification requirements for an uniform level of safety, but Special 

Conditions previously issued by the FAA have only two (2) requirements. 

29.1045 Hover Cooling Test conditions 

29.1521 Powerplant Limitations 

The following requirements were added to this proposed SC when not present on previous 

helicopter SC such as 29-004-SC: 

29.1305(a)(25) Countdown Timer 

29.1521 Powerplant time limit per flight 

C d ... · ana a 

214 

,.'1 

lk_.:,,:, 
6139523298 13:51:07 08-02-2013 

As proposed as section (b) ofthis Special Condition 29-030-SC: 

A countdown timer is not required of 5 minutes Take-off power or 2.5-minute OEI or even 30-

rninute OEI power, it should not be required of a 30-minute AEO (All Engine Operating) power. 

It should be noted that a countdown timer is in lieu of instrument markings as per 29.1549(e) at 

Arndt 29-34 .. Ref: 

[(e) Each OE!limit or approved operating range must be marked to be clearly 

differentiated from the markings of paragraphs (a) through (d) of this section except that 

no marking is normally required (or the 30-second OE!limit.]. 

A countdown timer in lieu of an instrument marking is inappropriate for any rating of 2.5 

minutes or longer duration. 

The countdown timer is not provided in the engine Special Condition 33-0 10-SC for the PT6C67E. 

The whole section (b) as proposed should not be required on the EC l75B by Special Condition 

as it was not required previously on other USA helicopters. It should be removed. 

As proposed in section (c) of this Special Condition 29-030-SC: 

For powerplant limitations, 29.1521, in addition to the 30 minutes limit per use, a 50 minutes 

limit per flight is proposed. 50 minutes was not demonstrated and is not certified as an engine 

limit nor is required by FAA engine Special Condition. 30 minutes power rating for longer 

hovering does not need to be assured as HOGE is not required for continued safe flight and 

landing. The 30 minutes power does not cause accelerated damage on the engine nor require 

close monitoring to ensure continued airworthiness of the engine. A time limit per flight would 

cause regulatory problems should an operator mission be approved by the engine authority for 

more HOGE events, each less than 30 minutes per HOGE event, but for a total of more than 50 

minutes per flight. It would also be problematic if another engine model with a 30-minute power 

rating was installed on the EC 175B helicopter causing a difference (refer to EC 130T2). 

A 50 minutes per flight limit should not be required by Special Condition as it was not required 

previously on other USA helicopters. 

Overall and based on 29.1521(g), our suggestion is to replace both section (b) and (c) by: 

(b) Section 29.1521 Powerplant limitation, at Amendment 29-41. In addition to the requirements 

of this section, the special condition states: 

30 minute Power Operation. The powerplant operation must be limited to turbine powered 

rotorcraft with rated 30-minute power engines for no longer than 30 minutes per use. The use of 

the 30-minute power must also be limited by -

( 1) The maximum rotational speed, which may not be greater than-

(i) The maximum value determined by the rotor design; or 

(ii) The maximum value demonstrated during the type tests; 

(2) Th~ maximum allowable turbine inlet or turbine outlet gas temperature; 

(3) The maximum allowable power or torque for each engine, considering the power input 

limitations of the transmission with all engines operating; 

(4) The maximum allowable engine oil temperatures; and, 

(5) The maximum allowable transmission oil temperatures. 

2 

3/4 
6139523298 13:51:41 08-02-2013 

Thank you for this opportunity to comment on FAA Final Special Condition: Eurocopter France, 

EC 175B; Use of 30-Minute Power Rating- Part 29 

Should you require further information, please do not hesitate to contact Yves CousineauSenior Engineer, Powerplants and Emissions by phone at (613) 613-952-4413 or by email at 

Yves. Cousineau @tc.gc.ca. 

Yours truly, 

Aaron 

.. 

McCrone 

--.~~~~· · 

Director 

Standards Branch 

Transport Canada 

Copy: Mr. David Turnbull, Director- National Aircraft Certification Branch 

4/4