Date: 201301
Local time of day: 0601-1200
Location: OPF.Airport, FL
Flight conditions: VMC
Light: Daylight
Aircraft: Gulfstream IV / G350 / G450
Operating under: Part 91
Flight phase: Initial Climb; Climb
Airspace: Class B MIA; Class D OPF
ATC / advisory: Tower OPF
Reporter organization: Corporate
Reporter function: Pilot Not Flying; Captain
Human factors: Communication Breakdown
Second reporter function: Captain; Pilot Flying
Anomaly: ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: We were flying from to Palm Beach; Florida. We obtained clearance which was 'RADAR Vectors to Palm Beach; climb and maintain 2;000 feet.' We configured the aircraft altitude window for 2;000 feet and taxied for take off. When we were number one for take off; we were given the following clearance.' Taxi across the hold short line and taxi to the EDGE.' I responded with a line-up and wait response. The Tower Controller said he could not 'legally give us that clearance; taxi to the EDGE' (Phraseology I have never encountered in 40 years of flying. So; we stopped just before proceeding onto the runway at the 'edge' of initial side of the runway. We were then quickly cleared for takeoff and the takeoff was done normally and without incident. At about 1;200 feet in the straight out climb the Controller instructed us to 'Climb and maintain 5;000 feet; contact Miami approach.' I read back the climb to 5;000 feet; adjusted the altitude window and confirmed that we both had heard the same thing; and then switched to 'Departure.' When I did; I immediately recognized that we were on an ATIS frequency; so I toggled the radio back to Tower and asked him for the departure frequency again. At this point he told us that we were to maintain 2;000 feet; which we immediately began correcting to; and I quizzed him that he had cleared us to 5;000 feet to which he stated 'I never cleared you to 5000 feet.' He then gave us the departure frequency and we contact Miami departure. We looked at each other as we both clearly heard him say 5;000 feet; and I read back clearly 5;000 feet. By the time we had contacted Miami Departure; we had leveled at 2;000 feet. All of this occurred within 5 miles of the airport and less than 3;000 feet in altitude. Suggestions; easy; ensure that ATC controllers hear and understand the read back so that when they issue a wrong instruction; they can be caught in the read back of said wrong instruction.


Second narrative: Clearance was received from ATC with no problems. A flight crew briefing was preformed prior to take off and the route and ATC clearance was discussed. Cleared as filed; runway heading; RADAR vectors direct; initial altitude 2;000 feet; expect 5;000 feet 10 minutes after departure; Departure frequency 128.6; squawk XXXX. We called for taxi on time; we were instructed to taxi to Runway 27R; we were actually Number 2 for take off. ATC politely moved the aircraft after us. We taxied up to the hold short line for 27R; there was some non-standard communication from the OPF Tower; [and] he was talking/handling a couple of arrivals. He instructed us to 'line up and get close to the edge of the runway as we can.' Initially; I was confused with what ATC expected us to do; so I didn't taxi the airplane onto the runway; we asked for clarification. After the clarification; we taxied onto the runway; we were given an immediate take off clearance; 'without delay traffic 3 out.' We completed the lineup checklist and proceeded to take off uneventfully. ATC was busy; OPF Tower instructed us to contact MIA Departure at 1;000 feet; prior to changing (there was an initial statement from OPF Tower that our transponder wasn't working; which it was quickly verified ON and reporting) at this point they told us to maintain 5;000 feet and contact Departure on 125.9. The crew immediately questioned and verified the altitude change and verified the frequency with OPF Tower. Then told us; that is 'correct; maintain 5;000 feet and contact Departure. (The 125.9 frequency was OPF ATIS; subsequently) After 2-3 seconds; we heard the ATIS and returned to OPF Tower for a verification of the frequency. We were now at 3;200 feet; he promptly told us to descend to 2;000 feet and contact Miami Departure on 128.6. We complied with the descent. We politely informed OPF Tower; we queried the altitude and frequency change and he verified it; (the tower controller did initially and positively confirm the change). But now; OPF Tower denied he gave us a change in initial altitude and there was no mention of incorrect frequency assigned. We did not think it was prudent to push the issue on the frequency; we contacted MIA; they did not ask for clarification either. The rest of the flight was uneventful. OPF Tower did not ask us to contact them and neither did MIA. As far as crew was able to determine; no loss of separation horizontally or vertically was lost.


Synopsis: Corporate jet was question by ATC regarding assigned altitude; the reporter's insisting ATC issued the subject altitude.