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Tavaero Jet Charter Corp.

7930 Airport Blvd.

Houston, TX 77061

Phone: 713-643-5387

Fax: 713-640-2623

Email: maintenance@tavaero.com

Docket Management Facility

US Department of Transportation

1200 New Jersey Avenue, West Building Ground Floor W12-140

Washington, DC 20590

Subject: Tavaero Jet Charter Corp. Request for Exemption to Part 135 Appendix F- FDR 

Normal Acceleration parameters requirement for Challenger CL-600-2B16 (CL

604 variant) aircraft N456HK S/N 5568.

Dear Sir or Madam:

Tavaero Jet Charter request a time –limited exemption to Part 135 Appendix F- Airplane Flight 

Data Recorder (FDR) - Normal Acceleration parameter (#5) processing and recording 

requirements, on behalf of certain CL-6002B16 N456HK S/N 5568.

Executive Summary

Upon learning of a potential issue with one of the sampling parameters for the CL-604 aircraft 

operated under Part 135, Bombardier conducted an internal review which revealed noncompliance with a single sampling rate under Part 135, Appendix F. Specifically, it was 

discovered that the normal acceleration sampling rate is recorded by the FDR at the required rate 

of 0.125 seconds (8 times per second): however the source data is provided to the FDR at a rate 

of 0.2 seconds per sampling (5 times per second). As discussed below, the data can be correlated 

to match the sampling requirements without compromising the information recorded and all 87 

other parameters are being recorded at the range, accuracy, and sampling rates specified in 

Appendix F. Upon completing its investigation, Bombardier immediately began working on a 

comprehensive solution with its partners, Rockwell Collins, which is further described below.
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BA is fully aware that Part 135 applies to aircraft operators, not manufactures and that the FAA 

does not typically grant exemptions to manufactures for operational requirements. However 

much like Airbus, BA delivers aircraft to its US customers with the understanding that they can 

be under Part 135, if so desired by the customer. BA is committing to provide a comprehensive 

solution to close this issue for its US customers, which includes publication of a Service Bulletin 

to operators to replace the Data Concentrator Unit (DCU) in order to meet the sampling 

requirements.

Request for Exemption

Specifics Section and Extent of Relief Requested

In accordance with 14 CFR Part 11, Tavaero Jet Charter Corp. request an exemption from the 

Normal Accelerations parameter in Appendix F of Part 135.152 to permit sampling 5 times(0.2 

seconds per sampling interval) per second unit the DCU is updated to provide 8 times per second 

(0.125 seconds per sampling interval).

BA had reviewed its records and determined that CL-604 N456HK S/N 5568 aircraft is affected 

by this request.

An exemption will have no adverse impacts on safe operations of aircraft.

The FDR, and its recording parameters, are not required for operations of the aircraft. The FDR’s 

primary purpose is to support investigations in case of incidents.

The Normal Acceleration is provided thru the DCU-4002. The baseline Challenger 604 aircraft 

has 2 such units.

Given that the information can be effectively correlated with no substantive degradation in 

information, we respectfully submit that that this compliance issue does not affect safe operation 

of the aircraft or hinder potential investigation requiring the FDR data.

Bombardier and its Supplier, Rockwell Collins is committed to develop an in-service solution 

involving a re-design of the DCU on or before September 2014. Additionally, BA proposes a 

subsequent fleet retrofit period to account for parts availability and operator downtime 

requirements, for a completed retrofit within two years of the granted exemption.

The exemption is in the public interest

The technical solution to address the current situation is unviable for this group of aircraft at this 

time. Granting the Exemption will allow the operator to carry the number of passengers per their 

approval configuration, as opposed to restricting the number of allowed passengers to 9 or fewer.
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Condition and Implementation

As was the case with Exemption 10611 and 10611A, Tavaero Jet Charter Corp request that the 

FAA allow continued operations of the aircraft subject to conditions specified in the exemption, 

which Tavaero Jet Charter Corp. respectfully suggest would include the following conditions 

similar to those contained in the above referenced DFDR exemptions for Airbus and its 

operators.

 Requirements for each Affected US Operator desiring an exemption to submit to the 

FAA a request to use the exemption for affected aircraft (including supporting 

information such as a list of aircraft and acknowledgment of conditions in the exemption 

and basis for continued operations) within a specific period of time on not less than 90 

day of the issuance of the exemption.

 Provisions to allow the exemption to transfer to subsequent transfer of the aircraft, with 

the written approval of the FAA, which shall not be unreasonably withheld and shall be 

subject to compliance with the conditions of the exemption.

 Copies of the exemption to be retained by the operator, and requirements that a copy be 

sent to the NTSB and FAA in connection with any accident or incident involving the 

FDR: and

 Within 90 days of receipt of the BA Service Bulletin, the operator must provide its 

principle avionics inspector a scheduled for completion of the new installation within the 

time period of the exemption.

Publication in the Federal Register

Tavaero Jet Charter Corp. request that the FAA waive publication of this exemption request in 

the Federal Register. First, the exemption applies only to a limited number of BA manufactured 

aircraft and the request is not precedent setting, if granted. Second, any delay in acting on the 

petition would unnecessarily delay implementation of the solutions for Affected US Operators.

Contact information

Should the FAA require any additional information, please do not hesitate to contact:

Isaac Kirkpatrick

Tavaero Jet Charter Corp. 

7930 Airport Blvd

Houston, TX 77061

maintenance@tavaero.com

Thank you for your consideration of Tavaero Jet Charter Corp’s request.

Best Regards,

Isaac Kirkpatrick

Chief Inspector

Tavaero jet Charter Corp.