Regional Jet 200 ER/LR (CRJ200)
Flight Crew Air Transport Pilot (ATP)
No Specific Anomaly Occurred All Types
Air Traffic Control Issued New Clearance; Flight Crew Diverted
Equipment / Tooling
Flight was planned to ORF with the gear pinned down. I believe there was 8;400 lbs. of fuel on board the aircraft on the ramp. This was 3;000 lbs. over our Takeoff Fuel. The flight was filed to fly at an altitude of FL320 and was restricted by MEL to 250 knots indicated. We received a reroute from ATC when calling for our clearance. I called the dispatcher to inform them of the reroute; and clarified that the fuel performance had been calculated for an aircraft with the gear down the whole flight. The dispatcher ran the new fuel burn for the re-route with me on the phone; gave us a new takeoff fuel load about 10 lbs. higher than our old one. We made Amend 1 for the reroute and new fuel burn. The First Officer (FO) and I felt comfortable with this fuel load; since we knew the dispatcher had planned it for the gear down and we had about 3;000 extra pounds of fuel. We then de-iced the aircraft and headed on our way. During our climb it became apparent that we would not have the performance to reach the planned altitude of FL320. At about FL200 and up; we were climbing at 500 feet a minute and slowly loosing airspeed. Our airspeed never went below 220KIAS. We elected to stop the climb at FL240 and requested that altitude with ATC. ATC assigned us FL240 and we continued to cruise at that altitude at approximately 240-250KIAS. Our thrust was close to max cruise thrust; as this is what was required to maintain our airspeed. We were burning approximately 1;650 LBS per hour on each engine. By the time we were abeam BOS it became apparent that we were burning more fuel than had been planned. We were burning about 3;400 lbs. an hour; had approximately 6200 lbs. of fuel left on board; and about 1 hour and 50 minutes time remaining in the flight. At this point we began messaging our dispatcher that we would most likely need to divert to another airport; as we were not going to have the fuel to make it to ORF and land there with any sort of reserve. The dispatcher was initially hesitant to comply with our request for an alternate airport. We were not in an emergency fuel situation; and had about two hours of fuel left; so we agreed with the dispatcher to check the fuel again in 100 NM and make a decision then. In the interim the crew began planning for a possible diversion. Our route of flight was taking us close to the normal northeast arrival path for PHL. We looked at possible routing and calculated potential fuel burn to PHL. At that point we were flying direct EMJAY or ZIZZI. Both fixes were very close to BRIGS and the JIIMS2 into PHL. We were also at FL240; the altitude at which aircraft begin that arrival. The crew was fairly confident that if we did go to PHL; we would be given this arrival. Approximately 75NM after our initial discussion with dispatch we were at approximately 5;000 lbs. of fuel and still burning 3;400 lbs. an hour. We still had over 1 hour and 30 minutes left to ORF. We made the determination we would not be able to get to ORF; and messaged dispatched telling them as such; and asking that they amend our destination to PHL. Dispatch sent us Amend 2 designating PHL as the destination and we informed ATC we were changing our destination to PHL. ATC asked us the reason for the change; and we told them it was due to unplanned fuel burn.  We were cleared to PHL via radar vectors to BRIGS and the JIIMS2 arrival. About 20NM from BRIGS we determined that upon landing at PHL we would be right at our required alternate burn; and that we had just over an hour of fuel on board; given our current burn of 3;400-3;600 lbs. an hour. We had about 4;000 LBS of fuel on board at that time. We informed ATC that we were 'minimum fuel' at that point. ATC asked how much fuel in minutes was on board; and we came up with a conservative estimate of 60 minutes.  We proceeded to fly the arrival and land on Runway 26 in PHL without incident. We landed with approximately 2;300 lbs. of fuel on board.  On the next segment of flight PHL to ORF I called the dispatcher to discuss the fuel load. The planned cruising altitude for that flight was an 16;000. The planned Ramp Fuel was around 5400 lbs. I felt that this fuel load was not sufficient for a 50 minute flight with the gear down; taking our recent experience into consideration. I requested 9;000 LBS of fuel and the dispatcher agreed and created a new dispatch release with the revised ramp fuel. During that flight we still burned more fuel than was planned on the dispatch release. The planned fuel burn was 1;560 lbs. and we burned approximately 2;600 lbs. during the flight. We landed in ORF without further incident with approximately 6;200 lbs. of fuel. Had the Dispatcher had better information we may never have been planned at FL320. I'm hesitant to believe this alone would have prevented the diversion. I think that the fuel planning software used by our dispatcher inadequately calculated the fuel burn penalty for flight with the gear down. We left the ground 3;000 lbs. of above our Take Off fuel; this should have been enough to get us to our destination and then some. It was frustrating to the crew that the dispatcher needed so much convincing that we were not going to be able to make it to ORF. We tried to communicate our fuel on board; current burn; and time remaining; to show that it was becoming mathematically impossible to get to ORF. Our dispatcher did not seem to believe us at first.
Flight crew of a CRJ-200 repositioning flight for maintenance were planned for FL320; gear down flight at 250 KIAS. Enroute aircraft is only able to climb to FL240 max altitude thus dipping into their fuel reserves and forcing a diversion. Flight refuels and continues on to intended destination.