Date: 201807
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: Challenger 300
Operator: Air Taxi
Operating under: Part 135
Mission: Passenger
Flight phase: Parked
Reporter organization: Air Taxi
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Confusion; Training / Qualification
Anomaly: Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Weight And Balance; Ground Event / Encounter Other / Unknown
Detector: Person Flight Crew
When detected: Pre-flight
Result: Flight Crew Overcame Equipment Problem
Contributing factors: Company Policy; Airport; Human Factors; Manuals
Primary problem: Ambiguous

Narrative: Landed in ZZZ with approximately 5;900 lbs fuel remaining. I had previously determined through [flight planning software] that we could land with this amount. I was estimating an approximately 30;000 lbs takeoff on the next leg. I knew ZZZ was relatively short but we had flown out of ZZZ1 [a shorter runway] the previous day at a much warmer temperature and higher weight. Shortly after landing; our passengers arrived with lots of small lightweight items. They were approximately 25 minutes early and I had not yet done [flight planning]. My Copilot was working on the clearance and turnaround check so I assisted the passengers with their baggage. I returned to the cockpit to finish takeoff and CG calculations. With the weather at 090/09; 20C; 30.33 using RWY XX and a weight 30;500 lbs I was unable to get [flight planning software] to show numbers within limits. I changed the TO (Takeoff) weight several times in an attempt to determine what the limiting weight was but had no success. This made no sense to the Copilot or me. The FMS numbers showed sufficient runway and we didn't believe the small hill at the end of the runway would be a limiting factor. I decided to call [Operations] while Copilot worked the TO and CG problem with the aircraft manuals. I spoke with [Operations] and explained that I could not get [flight planning software] to give any TO numbers at any weight. [Operations] did his own calculations with [company] to derive numbers that allowed a TO weight of 29;900 lbs. I was also given the v speeds and other info to fill the [takeoff speed] card. In the meantime; the Copilot confirmed that the manually calculated numbers would allow us to depart on RWY XX also. We were slightly overweight at our present weight. I informed the passengers and FBO personnel that we would need to start both engines and burn down to a proper TO weight. It took about 20 minutes to reach the desired weight. We subsequently departed RWY XX without incident.Afterwards; the Copilot and I agreed that we should try to get an explanation as to why [flight planning software] had failed us. We decided that I should talk to someone in the Training Department to walk us through our calculations. I assumed that there was either a glitch in our App or that we had neglected to input some parameter. While continuing to try different scenarios with [flight planning software]; I determined that when using [limited features]; a limit weight of 30;471 lbs was available. I had also been going through the [manual] in attempt to understand more about [company] requirements and that's when I encountered ZZZ listed as a Special Operations airport.I did not know nor did I have any clear notification that ZZZ was a Special Use Airport. With prior knowledge; crew would have realized that the trip was not acceptable.




Synopsis: Challenger 300 Captain reported being unable to obtain runway takeoff data using preflight software; likely due to the selected runway not authorized by company policy.