Narrative:

While flying to paris, france (lfpg) we entered french airspace from the east at FL340 on a direct to fix clearance. After approximately 10 mins of french control, we were given descent instructions. I was acting as pilot not flying and the first officer was acting at pilot flying. As understood by us, the following instructions were given by ATC: 'air carrier X, descend to FL230.' 'air carrier X is leaving FL340 for FL230.' (FL230 is entered in fcp and confirmed by PNF.) a short pause. 'Air carrier X, descend to FL230.' we acknowledged, 'roger, air carrier X is descending to FL230.' when passing FL330, ATC asked, 'air carrier X, maintain FL230.' we responded again, 'air carrier X understands, descend to FL230.' ATC responded, 'negative, maintain FL230.' this is when we had a cockpit discussion. We responded, 'control, is the new, FL330?' and ATC responded with, 'affirmative.' climb was initiated by PF from FL32.8 back to FL330. No further comments from french ATC. In retrospect, I believe the controller was mixing french and english. I believe he was rapidly saying, 'descend to fl deux (2) three zero, meaning two threes and a zero.' at no time did myself or the PF(both very experienced international pilots) think that the controller was saying anything other than FL230. Callback conversation with reporter revealed the following information: after the controller questioned the flight crew a second time, the reporter said the crew began to question the apparent word 'two', realizing the controller was probably mixing french with english by using the french word 'deux.' the reporter stated the crew was a well seasoned international flight crew. The reporter stated that french controllers often mix control instructions between french and english in the same clearance as it happened in this incident.

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Original NASA ASRS Text

Title: FLT CREW IS CHALLENGED BY LFFF ARTCC RADAR CTLR WHEN OBSERVING CONTINUED DESCENT WHEN LEVEL OFF WAS EXPECTED. CTLRS FRENCH/ENGLISH PHRASEOLOGY MIX IS CAUSE OF ALT OVERSHOOT AS FLT CREW CLARIFY ALT ASSIGNMENT.

Narrative: WHILE FLYING TO PARIS, FRANCE (LFPG) WE ENTERED FRENCH AIRSPACE FROM THE E AT FL340 ON A DIRECT TO FIX CLRNC. AFTER APPROX 10 MINS OF FRENCH CTL, WE WERE GIVEN DESCENT INSTRUCTIONS. I WAS ACTING AS PLT NOT FLYING AND THE FO WAS ACTING AT PLT FLYING. AS UNDERSTOOD BY US, THE FOLLOWING INSTRUCTIONS WERE GIVEN BY ATC: 'ACR X, DESCEND TO FL230.' 'ACR X IS LEAVING FL340 FOR FL230.' (FL230 IS ENTERED IN FCP AND CONFIRMED BY PNF.) A SHORT PAUSE. 'ACR X, DESCEND TO FL230.' WE ACKNOWLEDGED, 'ROGER, ACR X IS DESCENDING TO FL230.' WHEN PASSING FL330, ATC ASKED, 'ACR X, MAINTAIN FL230.' WE RESPONDED AGAIN, 'ACR X UNDERSTANDS, DESCEND TO FL230.' ATC RESPONDED, 'NEGATIVE, MAINTAIN FL230.' THIS IS WHEN WE HAD A COCKPIT DISCUSSION. WE RESPONDED, 'CTL, IS THE NEW, FL330?' AND ATC RESPONDED WITH, 'AFFIRMATIVE.' CLIMB WAS INITIATED BY PF FROM FL32.8 BACK TO FL330. NO FURTHER COMMENTS FROM FRENCH ATC. IN RETROSPECT, I BELIEVE THE CTLR WAS MIXING FRENCH AND ENGLISH. I BELIEVE HE WAS RAPIDLY SAYING, 'DESCEND TO FL DEUX (2) THREE ZERO, MEANING TWO THREES AND A ZERO.' AT NO TIME DID MYSELF OR THE PF(BOTH VERY EXPERIENCED INTERNATIONAL PLTS) THINK THAT THE CTLR WAS SAYING ANYTHING OTHER THAN FL230. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: AFTER THE CTLR QUESTIONED THE FLT CREW A SECOND TIME, THE RPTR SAID THE CREW BEGAN TO QUESTION THE APPARENT WORD 'TWO', REALIZING THE CTLR WAS PROBABLY MIXING FRENCH WITH ENGLISH BY USING THE FRENCH WORD 'DEUX.' THE RPTR STATED THE CREW WAS A WELL SEASONED INTERNATIONAL FLT CREW. THE RPTR STATED THAT FRENCH CTLRS OFTEN MIX CTL INSTRUCTIONS BETWEEN FRENCH AND ENGLISH IN THE SAME CLRNC AS IT HAPPENED IN THIS INCIDENT.

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.