TBM850 instructor and student plan and request a practice emergency descent from ATC; starting from ...

Attributes
ACN	1204994
Time
Date	201409
Local Time Of Day	1201-1800
Place
Locale Reference	ZHU.ARTCC
State Reference	TX
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	TBM 700/TBM 850
Operating Under FAR Part	Part 91
Flight Phase	Descent
Route In Use	Vectors
Flight Plan	IFR
Component
Aircraft Component	Air/Ground Communication
Person 1
Function	Pilot Flying Trainee
Qualification	Flight Crew Rotorcraft Flight Crew Multiengine Flight Crew Instrument Flight Crew Flight Instructor Flight Crew Commercial Flight Crew Glider
Experience	Flight Crew Last 90 Days 75 Flight Crew Total 5500 Flight Crew Type 400
Person 2
Function	Instructor Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 24000 Flight Crew Type 840
Events
Anomaly	ATC Issue All Types Aircraft Equipment Problem Less Severe Deviation - Altitude Excursion From Assigned Altitude Deviation - Procedural Clearance

Narrative:

Simulated emergency descent I was taking 6 day recurrent training with a tbm 850 instructor. My instructor filed an IFR flight plan (from the air) in the vicinity of stv with houston center in order to climb on a heading to FL280 to practice a simulated emergency descent to 14;500. The practice simulated emergency descent procedure was approved by ATC with block altitudes and on a heading via radar vectors. I was in the left seat and my instructor was in the right seat. My instructor called out simulated 'master alarm' and 'cabin pressure' on the cas; I identified the problem and we both donned oxygen masks; had our headsets on and switched the headset microphone to the oxygen mask transmit position. Due to oxygen breathing noise; it was hard for me to hear my own voice because of breathing feedback. The instructor had agreed to handle all radio communications during my recurrent training. My instructor filed the IFR flight plan for the simulated emergency descent procedure. I reasonably expected him to continue using the radio to communicate with ATC. This was the understanding between us. The instructor thought he communicated with ATC that we were starting the procedure and vacating FL280; but (not known to us) the microphone in the instructor's oxygen mask did not work so ATC did not hear the instructor's radio transmission. We started the procedure and vacated FL280 for 14;000. We started down and when passing through FL270 ATC questioned our descent. We leveled off and climbed back to FL280. The controller said he did not hear our request to start the simulated emergency descent and to start down (vacate FL280). We explained to ATC what had happened. Then we requested to start the simulated emergency descent procedure with ATC and descended from FL280 to 14;500 without incident and terminated the simulated emergency descent maneuver and canceled IFR with houston center.

Original NASA ASRS Text

Title: TBM850 instructor and student plan and request a practice emergency descent from ATC; starting from FL280. Oxygen mask noise prevents proper communication with ATC and the descent is initiated without approval.

Narrative: Simulated Emergency Descent I was taking 6 day recurrent training with a TBM 850 instructor. My instructor filed an IFR flight plan (from the air) in the vicinity of STV with Houston Center in order to climb on a heading to FL280 to practice a simulated emergency descent to 14;500. The practice simulated emergency descent procedure was approved by ATC with block altitudes and on a heading via radar vectors. I was in the left seat and my instructor was in the right seat. My instructor called out simulated 'master alarm' and 'Cabin Pressure' on the CAS; I identified the problem and we both donned oxygen masks; had our headsets on and switched the headset microphone to the oxygen mask transmit position. Due to oxygen breathing noise; it was hard for me to hear my own voice because of breathing feedback. The instructor had agreed to handle all radio communications during my recurrent training. My instructor filed the IFR flight plan for the simulated emergency descent procedure. I reasonably expected him to continue using the radio to communicate with ATC. This was the understanding between us. The instructor thought he communicated with ATC that we were starting the procedure and vacating FL280; but (not known to us) the microphone in the instructor's oxygen mask did not work so ATC did not hear the instructor's radio transmission. We started the procedure and vacated FL280 for 14;000. We started down and when passing through FL270 ATC questioned our descent. We leveled off and climbed back to FL280. The controller said he did not hear our request to start the simulated emergency descent and to start down (vacate FL280). We explained to ATC what had happened. Then we requested to start the simulated emergency descent procedure with ATC and descended from FL280 to 14;500 without incident and terminated the simulated emergency descent maneuver and canceled IFR with Houston Center.

Data retrieved from NASA's ASRS site 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.