Narrative:

I was working sector xxra. Mr X. Was working the r-side. A B737 asked for a clearance direct ZZZ. Then he said he was declaring an emergency; and then he said something that was unintelligible at the time. For the duration of this situation; the B737 used unknown terms and did not speak clearly. The r-side asked for repeats and clarifications multiple times. The r-side cleared the B737 20 degrees left and to expect ZZZ in just a moment. At this time I physically got up to get the attention of the front line manager (flm). I explained to him we had an emergency. I requested a flight strip and told him the aircraft was diverting to ZZZ. I heard the B737 asking for lower and r-side referencing traffic. I mentioned to the r-side that perhaps the aircraft needed lower due to a problem such as pressurization. He then asked the B737 to verify it was not an aircraft emergency but personnel one. B737 said it was an aircraft emergency. Right next to us; sector zz had already approved a point out on the aircraft. I called sector ww to point out the emergency and asked how low he could descend. They released to FL190. When I came back to the frequency; the B737 was describing that the passengers and flight attendants could smell smoke in the cabin but did not have a fire indicator light. I passed this information to the flm and then to sector ww. The B737 asked what runway they were using at ZZZ. The r-side decided to bypass sector ww and go straight to sector yy. I called sector ww to tell them. I called sector yy to pass the information and request the runway at ZZZ. While waiting on that and back on frequency; the B737 asked for (emergency) equipment to be standing by and to inform them of smoke in the cargo bay; but not to approach the aircraft until he had spoke with them. I passed this information to the flm and sector yy. Then the r-side shipped the B737 to sector yy. Recommendation; I understand the pilot had a lot going. He was trying to determine what his situation was and trying to relay that to us. However; he did not make the nature of his emergency clear to us. The r-side had to make the pilot repeat several transmits. In his initial routing request and declaring an emergency he said a third thing that was unintelligible. When listening to the tape after the event; three people repeated the tape multiple times before we understood he was saying he had smoke on board. Obviously this was important for us to know. Likewise; he kept making reference to a 'three to one'. Originally we thought he was abbreviating his request for flight level three one zero. We never knew what he was referring to; but assumed it had something to do with his descent rate versus distance left to fly. I feel everyone involved made the attempt to handle this emergency to the best they could.

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Original NASA ASRS Text

Title: Enroute Controller and Flight Dispatcher recount an emergency declaration event noting the confusion experienced by ATC because of the lack of information provided by the flight crew.

Narrative: I was working Sector XXRA. Mr X. was working the R-side. A B737 asked for a clearance direct ZZZ. Then he said he was declaring an emergency; and then he said something that was unintelligible at the time. For the duration of this situation; the B737 used unknown terms and did not speak clearly. The R-Side asked for repeats and clarifications multiple times. The R-Side cleared the B737 20 degrees left and to expect ZZZ in just a moment. At this time I physically got up to get the attention of the Front Line Manager (FLM). I explained to him we had an emergency. I requested a flight strip and told him the aircraft was diverting to ZZZ. I heard the B737 asking for lower and R-Side referencing traffic. I mentioned to the R-Side that perhaps the aircraft needed lower due to a problem such as pressurization. He then asked the B737 to verify it was not an aircraft emergency but personnel one. B737 said it was an aircraft emergency. Right next to us; Sector ZZ had already approved a Point Out on the aircraft. I called Sector WW to point out the emergency and asked how low he could descend. They released to FL190. When I came back to the frequency; the B737 was describing that the passengers and Flight Attendants could smell smoke in the cabin but did not have a fire indicator light. I passed this information to the FLM and then to Sector WW. The B737 asked what runway they were using at ZZZ. The R-Side decided to bypass Sector WW and go straight to Sector YY. I called Sector WW to tell them. I called Sector YY to pass the information and request the runway at ZZZ. While waiting on that and back on frequency; the B737 asked for (emergency) equipment to be standing by and to inform them of smoke in the cargo bay; but not to approach the aircraft until he had spoke with them. I passed this information to the FLM and Sector YY. Then the R-Side shipped the B737 to Sector YY. Recommendation; I understand the pilot had a lot going. He was trying to determine what his situation was and trying to relay that to us. However; he did not make the nature of his emergency clear to us. The R-Side had to make the pilot repeat several transmits. In his initial routing request and declaring an emergency he said a third thing that was unintelligible. When listening to the tape after the event; three people repeated the tape multiple times before we understood he was saying he had smoke on board. Obviously this was important for us to know. Likewise; he kept making reference to a 'three to one'. Originally we thought he was abbreviating his request for flight level THREE ONE zero. We never knew what he was referring to; but assumed it had something to do with his descent rate versus distance left to fly. I feel everyone involved made the attempt to handle this emergency to the best they could.

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.