Narrative:

While on short final approach for landing on runway 26 at iah (1000 ft AGL), the houston tower cleared another company aircraft from the run-up block for an immediate takeoff on runway 26. At 300 ft AGL the tower realized the conflict with the departing aircraft and ordered my flight to go around with no missed approach instructions. We initiated a straight-out missed approach and at 1000 ft MSL I asked the tower for missed approach instructions. The tower said 'turn right heading 060 degrees and climb to 3000 ft.' at 2800 ft the tower said 'air carrier X, I told you to climb to 2000 ft.' I said 'no, you told us 3000 ft.' the tower then said 'descend to 2000 ft.' I acknowledged the clearance and we began a descent to 2000 ft. At 2600 ft another controller came on and said 'climb to 3000 ft.' we then climbed to 3000 ft and returned for a normal approach and landing. While in the middle of the go around, we were almost directly above the departing aircraft that was also in a right turn to 360 degrees. At the time we were at 2800 ft and the controller said 'I told you to climb to 2000 ft,' we were separated by only 900 ft on the TCASII. If we had leveled at 2000 ft, we would have come extremely close to an near midair collision with the departing aircraft. Because of the conflict there is no way we could have safely leveled off at 2000 ft. Miscellaneous details: several different voices were coming from the tower -- not just 1 controller. The departing aircraft on climb out was also experiencing miscoms with the tower.

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Original NASA ASRS Text

Title: B737 FLC AND IAH LCL CTLR CHALLENGE EACH OTHER ON CORRECT ALT ASSIGNED ON GAR CAUSED BY INCORRECT SPACING BTWN LNDG AND DEPARTING TFC.

Narrative: WHILE ON SHORT FINAL APCH FOR LNDG ON RWY 26 AT IAH (1000 FT AGL), THE HOUSTON TWR CLRED ANOTHER COMPANY ACFT FROM THE RUN-UP BLOCK FOR AN IMMEDIATE TKOF ON RWY 26. AT 300 FT AGL THE TWR REALIZED THE CONFLICT WITH THE DEPARTING ACFT AND ORDERED MY FLT TO GO AROUND WITH NO MISSED APCH INSTRUCTIONS. WE INITIATED A STRAIGHT-OUT MISSED APCH AND AT 1000 FT MSL I ASKED THE TWR FOR MISSED APCH INSTRUCTIONS. THE TWR SAID 'TURN R HDG 060 DEGS AND CLB TO 3000 FT.' AT 2800 FT THE TWR SAID 'ACR X, I TOLD YOU TO CLB TO 2000 FT.' I SAID 'NO, YOU TOLD US 3000 FT.' THE TWR THEN SAID 'DSND TO 2000 FT.' I ACKNOWLEDGED THE CLRNC AND WE BEGAN A DSCNT TO 2000 FT. AT 2600 FT ANOTHER CTLR CAME ON AND SAID 'CLB TO 3000 FT.' WE THEN CLBED TO 3000 FT AND RETURNED FOR A NORMAL APCH AND LNDG. WHILE IN THE MIDDLE OF THE GAR, WE WERE ALMOST DIRECTLY ABOVE THE DEPARTING ACFT THAT WAS ALSO IN A R TURN TO 360 DEGS. AT THE TIME WE WERE AT 2800 FT AND THE CTLR SAID 'I TOLD YOU TO CLB TO 2000 FT,' WE WERE SEPARATED BY ONLY 900 FT ON THE TCASII. IF WE HAD LEVELED AT 2000 FT, WE WOULD HAVE COME EXTREMELY CLOSE TO AN NMAC WITH THE DEPARTING ACFT. BECAUSE OF THE CONFLICT THERE IS NO WAY WE COULD HAVE SAFELY LEVELED OFF AT 2000 FT. MISC DETAILS: SEVERAL DIFFERENT VOICES WERE COMING FROM THE TWR -- NOT JUST 1 CTLR. THE DEPARTING ACFT ON CLBOUT WAS ALSO EXPERIENCING MISCOMS WITH THE TWR.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.