Date: 201706
Local time of day: 1201-1800
Location: EWR.Airport, NJ
Light: Daylight
Aircraft: Embraer Jet Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise; Taxi
Airspace: Class E ZNY
ATC / advisory: Center ZNY
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown; Training / Qualification
Anomaly: ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR; Inflight Event / Encounter Fuel Issue
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Diverted; Flight Crew Landed As Precaution
Contributing factors: Human Factors; Procedure; Company Policy
Primary problem: Ambiguous

Narrative: Prior to pushback; as is normal procedure; the clearance for our flight was obtained from Clearance Delivery. Our initial clearance was to expect our filed altitude of FL300. During taxi out; Newark ground control asked us to contact clearance delivery for a new routing. We were on taxiway Bravo holding short of Golf with brakes set. The first officer contacted Clearance Delivery and I; the PIC; monitored as well as copied the new routing as did the first officer. There was no mention of any altitude changes for our new route of flight mentioned. Once the clearance was confirmed; the first officer and I worked together to verify the route and input into the FMS. The new route was checked for accuracy; time; distance and fuel. The new route appeared to slightly improve our time; distance and fuel performance upon arrival at destination as compared to the original routing. The first officer and I agreed on the new routing and advised ground control. Once we departed; we were cleared to level off at 6000 ft. After a few minutes time; we began to inquire with ATC about when we could expect higher. ATC advised us that 6000 ft would be our final altitude. We further inquired and were informed that we had accepted clearance for a 'Sermon South' route and would not be given higher. They also informed us that our company had agreed to use 'Sermon South' routes which is why we were assigned the clearance. The first officer nor I had ever heard of 'Sermon South' routes and were perplexed by this. Newark Clearance Delivery had never made and mention of a 'Sermon South' route nor the fact that we would be required to maintain 6000 ft for the majority of the cleared route. Prior to takeoff and up until we were notified of the 'Sermon South' routes; both the first officer and I believed we would be cleared to our filed flight plan altitude of FL300 (as per the initial clearance) and had no indication from anyone that our final altitude would be limited to 6000 ft. I immediately began making fuel calculations and communicating with Dispatch about our situation. I also advised ATC of the fact that if we were limited to 6000 ft; we would not have enough fuel to legally make it to the destination and we would be diverting. ATC did attempt to make some concessions and eventually cleared us to 16000 feet; then to FL200. Even with the higher altitudes; the calculations revealed that we had consumed too much fuel at the lower altitudes for us to safely proceed to destination. Dispatch and I agreed to divert the flight to refuel.Newark Clearance Delivery was under high pressure to re-route numerous aircraft and may have inadvertently omitted the fact that they were clearing us for a route at 6000 ft. It is imperative to advise the crew of a turbojet aircraft that they are being re-routed to a significantly lower altitude than originally cleared for as fuel consumption rates at 6000 ft are significantly different than at FL300. Additionally; if those routed are to be used; there should be some sort of education granted to pilots who will be operating them prior to assigning the routes. Lastly; in the future; when I receive such a large re-route; I will also confer with dispatch prior to departure to ensure an incident like this is not repeated.




Synopsis: ERJ Captain reported receiving a reroute prior to departure from EWR which appeared shorter than the original route. Once airborne the crew learned of an altitude restriction that consumed additional fuel; resulting in a diversion.