Dhc-8-100 flight crew discovered incompatibility with ATOG procedures off gravel surfaced runways.

Attributes
ACN	1354752
Time
Date	201605
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Dash 8-100
Operating Under FAR Part	Part 121
Flight Phase	Takeoff
Flight Plan	IFR
Person 1
Function	Pilot Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Deviation - Procedural FAR Deviation - Procedural Published Material / Policy Deviation - Procedural Weight And Balance

Narrative:

Takeoff out of ZZZ was completed using the company provided ATOG for departure off runway 31 with tailwind calculations completed and at an approved weight. After departure I felt there may have been a compatibility issue and during cruise I looked in the afm and discovered supplement 3 is not compatible with supplement 26. Which means operations in tailwinds between 10-20kts cannot be conducted on gravel runways. There is absolutely no reason there should be atogs provided to crewmembers for tailwind operations from a gravel runway when this is not valid. This is a trap the company has overlooked apparently and the tailwind notes for 10-20 should be removed from the atogs completely and immediately to prevent other crews from this circumstance.

Original NASA ASRS Text

Title: DHC-8-100 flight crew discovered incompatibility with ATOG procedures off gravel surfaced runways.

Narrative: Takeoff out of ZZZ was completed using the company provided ATOG for departure off runway 31 with tailwind calculations completed and at an approved weight. After departure I felt there may have been a compatibility issue and during cruise I looked in the AFM and discovered supplement 3 is not compatible with supplement 26. Which means operations in tailwinds between 10-20kts cannot be conducted on gravel runways. There is absolutely no reason there should be ATOGS provided to crewmembers for tailwind operations from a gravel runway when this is not valid. This is a trap the company has overlooked apparently and the tailwind notes for 10-20 should be removed from the ATOGS completely and immediately to prevent other crews from this circumstance.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.