Narrative:

Clearance delivery assigned us the hedly departure from mia with an altitude restriction of 5000. Ground control gave us the instructions 'taxi to runway 8L but have your numbers for runway 12 as well'. Holding short of 8L we contacted tower and he said 'cross 8L and hold short of 8R; I am planning on giving you a 90 heading'; however it was never issued in the form of a formal clearance; just what he was 'planning'. Tower next said 'you will have moderate precipitation east of the field; can you accept 8R?' we replied 'yes'. The next instruction from the tower was 'cleared for takeoff 8R'. (I heard nothing further in the way of a 'clearance' or heading) and read back 'cleared for takeoff 8R'. The only true clearance we were still operating under was the hedly departure. After takeoff; departure control assigned us 7000 ft. Shortly after this the aircraft began the turn from senoy to cimba on the departure. As we were climbing through 6100 on our way to 7000 departure control instructed us to 'maintain 6000'; to which we responded 'we just passed six on our way to seven but will descend to six'. Departure responded 'just climb and maintain 7000'. Within about 15 seconds departure control wanted to know our heading. We responded that we were in the turn from senoy to cimba. After this they gave us a heading of 360 and after we had leveled at 7000 he pointed out traffic to our right and directed us to fly a heading of 270. From here on everything proceeded uneventfully with a couple heading changes to avoid weather and stepping us up towards our filed altitude. Never was there mention of any navigation deviation.

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Original NASA ASRS Text

Title: A C560 flight crew took off without a clear understanding of their clearance.

Narrative: Clearance delivery assigned us the HEDLY departure from MIA with an altitude restriction of 5000. Ground control gave us the instructions 'taxi to Runway 8L but have your numbers for Runway 12 as well'. Holding short of 8L we contacted Tower and he said 'cross 8L and hold short of 8R; I am planning on giving you a 90 heading'; however it was never issued in the form of a formal clearance; just what he was 'planning'. Tower next said 'you will have moderate precipitation east of the field; can you accept 8R?' We replied 'yes'. The next instruction from the tower was 'cleared for takeoff 8R'. (I heard nothing further in the way of a 'clearance' or heading) and read back 'cleared for takeoff 8R'. The only true clearance we were still operating under was the HEDLY departure. After takeoff; departure control assigned us 7000 FT. Shortly after this the aircraft began the turn from SENOY to CIMBA on the departure. As we were climbing through 6100 on our way to 7000 departure control instructed us to 'maintain 6000'; to which we responded 'we just passed six on our way to seven but will descend to six'. Departure responded 'just climb and maintain 7000'. Within about 15 seconds Departure Control wanted to know our heading. We responded that we were in the turn from SENOY to CIMBA. After this they gave us a heading of 360 and after we had leveled at 7000 he pointed out traffic to our right and directed us to fly a heading of 270. From here on everything proceeded uneventfully with a couple heading changes to avoid weather and stepping us up towards our filed altitude. Never was there mention of any navigation deviation.

Data retrieved from NASA's ASRS site as of April 2012 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.