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This document is the intellectual property of DASSAULT AVIATION. It may not be used, reproduced, modified or disclosed without its authorization. DASSAULT AVIATION Proprietary Data. DIRECTION GÉNÉRALE TECHNIQUE Mérignac, October 23 r d , 2014

DGT-DTC/CEP 369796

RL/FA

TO :

Federal Docket Management System (transmitted electronically)

Please contact Rémy LAMELOT Tél : +33 (0) 556 13 4156 Fax : +33 (0) 556 13 9187

SUBJECT: Falcon 7X Series - Petition fo r exemption regarding 14 CFR Part 25.1447(c)(1) Applicable to: passenger oxygen dispensing units



### 1. Name and Address of the Petitioner [as per 14 CFR 11.81 a]

Rémy Lamelot, Certification Manager

Dassault Aviation

54 avenue Marcel Dassault – BP 24 33701 Mérignac Cedex, France

Phone: +33 556 13 4156 Email: remy.lamelot@dassault-aviation.com



### 2. Specific Section from wh ich Exemption is Sought [as per 14 CFR 11.81 (b)]

To whom it may concern:

DASSAULT AVIATION is officially applying for a permanent exemption to the following rule: 14 CFR Part 25.1447(c)(1).

14 CFR section 25.1447(c)(1) requires that “there must be an oxygen dispensing unit connected to oxygen supply terminals immediately available to each oc cupant, wherever seated”. It further states in part that “If certification for ope ration above 30,000 feet is requeste d, the dispensing units providing the required oxygen flow must be automatically presen ted to the occupants before the cabin pressure altitude exceeds 15,000 feet.”



### 3. Summary of the Petition [as per 14 CFR 11.81 (f)]

In accordance with the provisions of 14 CFR 11.81, DASSAULT AVIATION respectfully petitions for a permanent exemption from FAR 25.1447(c)(1) to allow the installation of a passenger oxygen system which, when operating into or out of an airf ield with a pressure altitu de greater than 14,000 ft but lesser than 15,000 ft, ensures the automatic pres entation of oxygen dispen sing units to occupants

before cabin altitude exceed s 16,000 ft, rather than 15,000 ft as required per FAR 25.1447(c)(1).09004000808007dd - RELEASED - Certification RepositoryDGT-DTC/CEP 369796 2/5

This document is the intellectual property of DASSAULT AVIATION. It may not be used, reproduced, modified or disclosed without its authorization. DASSAULT AVIATION Proprietary Data. When operating into or out of an airfield with a pressure altitude less than or equal to 14,000 ft, the oxygen system complies with FAR 25.1447(c)(1) and ensures that passengers oxygen masks are automatically presented before cabin altitude reaches 15,000 ft.

In support of this request, DASSAULT AVIATION is proposing alternative design requirements to provide a level of safety appropriate to the operation of Falcon 7X aircraft on airfields with pressure altitude up to 15,000 ft. DA proposition ta kes benefit from previous certif icates of exemption issued by FAA that permit the installation of an oxygen sy stem with a setpoint higher than 15,000 ft for automatic presentation of oxygen masks.



### 4. Background / Extent of relief and reason [as per 14 CFR 11.81(c)]

Dassault Aviation has submitted an application for FAA validation of a type design change to the Falcon 7X model aircraft to allow op erations into / out of airfields up 15,000 ft pressure altitude. This project is managed under change number M1315. The US certification basis fo r F7X is 14 CFR part 25, effective February 1, 1965, including Amendments 25-1 through 25-111 in en tirety as documented in Type Certification Data Sheet A59NM.

The Falcon 7X Series is designed to meet the re quirements of 14 CFR Part 25 for Transport Category

aircraft. These rules were written at a time when all airfields accessibl e to such aircraft were located below 14,000 ft. As a result, the aircraft cabin altitude was never supposed to reach 15,000 ft under normal circumstances, and having an oxygen system that automatically presents oxygen masks when cabin altitude reaches 15,000 ft was an adequate compromise between occupants’ safety and the conduct of operations on hi gh-altitude airfields.

The Falcon 7X is already certified for high La nding Field Elevation operations, with a maximum airfield pressure alti tude of 14,000 ft. However a few airfie lds with a LFE between 14,000 ft and 15,000 ft above mean sea level exist in the Chinese regions of Tibet and Sichuan. This means that under standard atmospheric conditions, pressure altit ude on these airfields wi ll be between 14,000 ft and 15,000 ft. These airfields are accessibl e to Transport Category aircraft.

When operating out of or into such airfields, the cabin altitude may thus reach values close to or even equal to 15,000 ft before takeoff or after landing. This could result in unwanted presentation of oxygen masks and the need for a maintenance operation in or der to store them back into their boxes, plus a possible cancellation or dela y of the planned flight.

The change proposed is designed to maintain an equivalent level of safety while minimizing the possibility of such unwanted deployment of oxygen masks.

The current design of the passenger oxygen system ha s one pressure altitude setpoint of 14,500 ft +/- 500 ft (accounting for sensor tolerance), thus ensu ring automatic presentation of oxygen masks before cabin altitude reaches 15,000 ft.DGT-DTC/CEP 369796 3/5

This document is the intellectual property of DASSAULT AVIATION. It may not be used, reproduced, modified or disclosed without its authorization. DASSAULT AVIATION Proprietary Data. In the proposed design, a second setpoint of 15,500 ft +/- 500 ft is implemented in the oxygen system. The Cabin Pressure Control System automatically commands the Oxygen System to use this second setpoint when aircraft pressure altitude is belo w 24,800 ft and one of the following conditions is true:

- Aircraft is on ground and aircraft pr essure altitude is above 14,000 ft, OR

- Aircraft is in climb and the pressure al titude at take off was above 14,000 ft, OR

- Aircraft is in descent and the selected Landing Field Elevati on is above 14,000 ft. Under all other conditions, the mask deployment setpoint remains at th e current value i.e. 14,500 ft +/-

500 ft.

The manual mask deployment control (“Overrid e” position of the oxygen control rotactor) is unchanged and remains available at any mo ment whatever the setpoint value.

Note that the maximum cabin pressure altitude r eached in flight under norma l operating conditions is not modified compared to current certified de sign, which was found compliant with FAR 25.841 (a). When takeoff airfield pressure altitude is between 14,000 ft and 15,000 ft, the cabin pressure control system will pre-pressurize the aircra ft before take-off and set the cabin pressure altitude to 13,542 ft (same value as today when operating from a 14,000 ft airfield). During climb, the CPCS will let the cabin pressure increase, ensuring that a cabin altit ude not more than 7,950 ft is reached before the aircraft climbs above 25,000 ft pressure altitude. This behavior is identical to current design already certified for operations up to 14,000 ft airfield altitude.

As a result, the setpoint for the cabin high altit ude warning CAS message is unchanged and remains set at 14,200 ft for high LFE operations. The high cabin alt itude warning is inhibited on ground in order to avoid nuisance warnings. The high ca bin altitude warning se tpoint is reset to th e normal value of 8,000

ft when the aircraft altitude c limbs above 24,800 ft. This feature (cha nging the setpoint of the cabin altitude warning message) is already part of the existing design for high LFE operations.

Conversely, when LFE is between 14,000 ft and 15,000 ft , the CPCS will keep ca bin pressure altitude below 7,950 ft until the ai rcraft descends below 24,800 ft pressure altitude. At that point, the high altitude warning threshold will be shifted from 8,000 ft to 14,200 ft, and the CPCS will let the cabin pressure altitude increase until it reaches 13,542 ft . The CPCS will keep the aircraft pressurized at 13,542 ft cabin pressure altitude unt il landing is completed. This behavi or is identical to the existing aircraft when landing at an airf ield with LFE equal to 14,000 ft.

As a result, this proposed design change does not de grade the level of safety as far as FAR 25.841 (a)

is concerned. It will be demonstrat ed by System Safety Analysis that cabin pressure altitude always remains below 15,000 ft under any reas onably probable failure condition.



### 5. Public Interest [as per 14 CFR 11.81(d)]

DASSAULT AVIATION performs the completion and interi or furbishing of most of the aircraft it produces in Dassault Falcon Jet manufacturing plant of Little Rock, AR. Falcon ai rcraft are fitted with many products such as avionics, a uxiliary power units, en vironmental control systems, from several suppliers based in the United States. The exemption will directly impact the utility of the Falcon 7X for high-altitude operations and will allow fulfilling an explicit request from customers for such capability, thus having a direct effect on sales. These extra sales will benefit the economy in all

communities where Dassault Falcon Jet and its suppliers are located, whic h is in the public interest.DGT-DTC/CEP 369796 4/5

This document is the intellectual property of DASSAULT AVIATION. It may not be used, reproduced, modified or disclosed without its authorization. DASSAULT AVIATION Proprietary Data. 

### 6. Reasons why granting the exemption will not adversely affect safety [as per 14 CFR 11.81(e)]

The safety features described above (cf. §4) will ensure the avoidance of unwanted oxygen mask deployment during operations on high altitude airpor ts, while still providing for automatic deployment in case of cabin depressurization or lack of pressurization (the highest possible cabin altitude for mask deployment being 16,000 ft), and for manual deploymen t in case of failure of the automatic mode.

It will be demonstrated by System Safety Anal ysis that proposed design for pressurization and passenger oxygen systems meets or exceeds all failure probability requirements.

The exemption requested would thus have no adverse impact on current level of safety for the Falcon

7X aircraft.



### 7. Additional information [as per 14 CFR 11.81(g)]

In the scope of this petition, DASSAULT AVIATION ta kes benefit from previous grant of exemptions issued by FAA dealing with the setting of oxygen mask deploymen t setpoint above 15,000 ft for high airfield operations. Please note that FAA has previously granted such exemptions to several models with much larger passenger capacity than the DASSAULT Falcon 7X Series.

Exempt.

No Issue Date Expir.

Date FAA

Office Disp. Regulation Petitioner Aircraft

6076 04/26/1995 (NoExpire) (NA) Granted 25.841(a) 25.1447(c)(1) The Boeing Company B757

6994 09/16/1999 (NoExpire) (NA) Partially

Granted 25.1447(c)(1) Airbus

Industrie A319, A320, A321

8668 12/02/2005 (NoExpire) (NA) Granted 25.1447(c)(1) The Boeing Company B737

9801 12/12/2008 (NoExpire) (NA) Granted 25.1447(c)(1) The Boeing Company B787

10044 04/01/2010 (NoExpire) (NA) Granted 25.1447(c)(1) Gulfstream Aerospace Corporation GIV-X

GV-SP



### 8. Request for waiver from publication and comments [as per 14 CFR 11.87]

Considering the above listed exemptions, it is Da ssault Aviation opinion that the requested exemption is identical to exemptions granted previously and th at granting this petition would not set a precedent. As a result Dassault Aviation respec tfully requests that action on this petition should not be delayed by publication and comment procedures.DGT-DTC/CEP 369796 5/5

This document is the intellectual property of DASSAULT AVIATION. It may not be used, reproduced, modified or disclosed without its authorization. DASSAULT AVIATION Proprietary Data. 

### 9. Exercise of exemption privileges and Operation outside US [as per 14 CFR 11.81(h) and 11.83]

Considering the multitude of countries in which Fa lcon 7X Series are sold and operated, it is very likely that this exemption should be recognized by some other countries usually agreeing with FAA position.

Moreover, all the existing airfield s with altitude higher than 14,000 ft are located outside the United

States. Dassault Aviation thus re quests extension of this exemption outside the United States.



### 10. Conclusion

Dassault Aviation believe that the above argumen ts favor an exemption from 14 CFR 25.1447(c)(1) that would allow operations into / out of airfield s up to 15,000 feet for F7X aircraft. Additionally, Dassault Aviation believes that such an exemption is in the public interest and does not adversely affect current level of safety of the aircraft.

Please do not hesitate to ask for any additional information which you may require in order to respond to this petition.

Respectfully submitted,

Rémy LAMELOT Laurent FRANZONI Certification Manager F7X Program Certification Manager

Evidence of signature is provided by a red electronic stamp on the first page left hand margin.