Instructor with student pilot makes takeoff without clearance.

Attributes
ACN	299693
Time
Date	199503
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : det
State Reference	MI
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : instructional
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	climbout : takeoff
Flight Plan	None
Person 1
Affiliation	Other
Function	instruction : instructor
Qualification	pilot : instrument pilot : cfi pilot : commercial
Experience	flight time last 90 days : 100 flight time total : 1600 flight time type : 700
ASRS Report	299693
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : student
Events
Anomaly	incursion : runway
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact
Consequence	faa : reviewed incident with flight crew Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While taxiing back to takeoff on runway 33 at det, we asked for an intersection takeoff at hotel intersection, because of IFR traffic blocking the taxiway in front of us. The tower told us that the intersection departure was approved. We took off with no further conversation with the tower and on our downwind, the tower controller told us we had not been cleared for takeoff. She asked for no type of correction and we completed our landing with no problems. No traffic was disrupted by our departure. I do think that 1 of the problems was the fact that we didn't switch to the ground frequency while taxing back for departure.

Original NASA ASRS Text

Title: INSTRUCTOR WITH STUDENT PLT MAKES TKOF WITHOUT CLRNC.

Narrative: WHILE TAXIING BACK TO TKOF ON RWY 33 AT DET, WE ASKED FOR AN INTXN TKOF AT HOTEL INTXN, BECAUSE OF IFR TFC BLOCKING THE TXWY IN FRONT OF US. THE TWR TOLD US THAT THE INTXN DEP WAS APPROVED. WE TOOK OFF WITH NO FURTHER CONVERSATION WITH THE TWR AND ON OUR DOWNWIND, THE TWR CTLR TOLD US WE HAD NOT BEEN CLRED FOR TKOF. SHE ASKED FOR NO TYPE OF CORRECTION AND WE COMPLETED OUR LNDG WITH NO PROBS. NO TFC WAS DISRUPTED BY OUR DEP. I DO THINK THAT 1 OF THE PROBS WAS THE FACT THAT WE DIDN'T SWITCH TO THE GND FREQ WHILE TAXING BACK FOR DEP.

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.