EMB ERJ 145 ER/LR
Flight Crew Air Transport Pilot (ATP)
Communication Breakdown; Confusion; Training / Qualification; Troubleshooting
Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Weight And Balance; Inflight Event / Encounter Weather / Turbulence; Inflight Event / Encounter Fuel Issue
Flight Crew Became Reoriented; Flight Crew Diverted
Manuals; Weather; Procedure
The flight was a ferry flight with no passengers or flight attendant. It was an empty aircraft with 1500 lbs of ballast fuel added. While holding; we calculated decision fuel by adding reserve 1800; burn to alternate 800; and a burn of about 200 lbs to the destination which gave us a decision fuel about around 2800 lbs. We held till we had 3800 lbs and I decided to divert to the alternate because the weather over our destination was not moving and it was becoming apparent that we were not going to have enough time to get in. Dispatch also advised us that the approximately 800 lbs burn was at 17000 ft altitude (we were at 12;000 ft). When we were enroute to the alternate; Dispatch advised us that we couldn't burn into the 1500 lbs of ballast fuel that we had. So our real reserve was not 1800 lbs but 3300 lbs. Since we were already on our way to the alternate at this point; and the weather was good; I made the decision to continue to the alternate. We landed with a little over 3000 lbs which was below the reserve fuel of 3300 lbs. There was confusion over whether our reserve fuel was 1800 lbs or 3300 lbs and we didn't realize it was the higher number till advised by Dispatch. Dispatch also advised me that their software doesn't account for ballast fuel when planning for decision fuel and as a result we were not advised of the higher number earlier during the flight. I contacted a few other pilots and there is definitely confusion over whether the ballast fuel is used for actual ballast or to 'trick' the weight and balance program to giving us a proper calculation. I will verify the release paperwork for the 'reserve' fuel number and not just assume it to be in the vicinity of 1800 lbs. I think the company should clarify the reason for the ballast fuel and specific requirements of the ballast fuel for empty flights as there seems to be confusion about it. In addition; pilots should be made aware of this potential for confusion. Because of the added stress of holding during weather events; the potential for this to be overlooked is greater.
An EMB-145 ferry flight with ballast fuel diverted because of poor destination weather after holding and learned ballast fuel cannot be burned as holding fuel.