CVR transcript United Air Lines Flight 553 - 08 DEC 1972
Cockpit voice recorder transcription of the December 8, 1972 crash of a United Air Lines Boeing 737 (Flight 553) at Chicago, IL.
Source: NTSB-AAR-73-16
Source: NTSB-AAR-73-16
The reader of these transcripts is cautioned that the transcription of a CVR tape is not a precise science but is the best possible product from a group investigative effort. The transcript, or parts thereof, if taken out of context can be misleading. Therefore, the CVR transcripts should only be viewed as an investigative tool to be used in conjunction with other evidence. Conclusions or interpretations should not be made using the transcript as the sole source of information.
Furthermore, this transcript is made available for educational purposes, so the reader is encouraged to read the accident description associated with the transcripts for better understanding of the circumstances.
Furthermore, this transcript is made available for educational purposes, so the reader is encouraged to read the accident description associated with the transcripts for better understanding of the circumstances.
Legenda
CAM - Cockpit area microphone
RDO - Radio transmission from accident aircraft
-1 - Voice identified as Captain
-2 - Voice identified as First Officer
-3 - Voice identified as Second officer
-? - Unidentifiable voice
CHI APP = Chicago Approach
MTWR = Chicago-Midway Tower
* - Unintelligible word
# - Expletive deleted
() - Questionable text
9VS = Aero Commander 690, N309VS pilot
RDO - Radio transmission from accident aircraft
-1 - Voice identified as Captain
-2 - Voice identified as First Officer
-3 - Voice identified as Second officer
-? - Unidentifiable voice
CHI APP = Chicago Approach
MTWR = Chicago-Midway Tower
* - Unintelligible word
# - Expletive deleted
() - Questionable text
9VS = Aero Commander 690, N309VS pilot
| time | source | content |
|---|---|---|
| 20.25:25.0 | CHI APP | Five five three, call the tower on one eighteen seven |
| 20.25:28.0 | RDO-2 | Eighteen seven, five five three |
| 20.25:35.5 | RDO-2 | Midway tower, United five five three, an' we'r out of three for two |
| 20.25:39.0 | MTWR | United five five three, report passing the outer marker, number two on the approach |
| 20.25:41.0 | CAM-3 | Chicago, this is five five three (2nd officer calling ARINC) |
| 20.25:44.0 | RDO-2 | Okay, report the outer marker |
| 20.25:46.5 | CAM-1 | Let's have the gear down please |
| 20.25:48.0 | RDO-1 | [Start of first sound of first series off Kedzie outer marker beacon tones] |
| 20.25:50.97 | CAM-3 | Chicago, five five three (2nd officer calling ARINC) |
| 20.25:51.62 | CAM | [Sound of a click - sound similar to sound of landing gear handle going into down detent] |
| CAM | [Sound of chime - simultaneous with click above] | |
| 20.25:52.20 | MTWR | Nine Victor Sugar, what's your airspeed? |
| 20.25:54.5 | [End sound of first series of Kedzie outer marker beacon tones] | |
| 20.25:54.74 | 9VS | Ah, we're down to ah, hundred twenty knots |
| 20.25:55.06 | CAM | [Increase in ambient noise level - similar to increase made by nose landing gear extended] |
| 20.25:56.82 | MTWR | Ah hundred and twenty, okay |
| 20.26:00.64 | CAM | [Sound of first of four clicks in rapid increase - sounds similar to flap lever moved from 15 degrees to 25 degrees position] |
| 20.26:01.50 | CAM-? | Gear 'own |
| CAM | [Sound of several clicks - similar to sound of stabilizer trim actuation] | |
| 20.26:10.02 | RDO-1 | [Sound of beginning of second series of Kedzie outer marker beacon tones] |
| 20.26:20.02 | RDO-1 | [End of sound of second series of Kedzie outer marker beacon tones] |
| 20.26:24.66 | CAM-1 | Final descent check |
| 20.26:25.66 | CAM-3 | Flight and nav |
| 20.26:27.11 | CAM-2 | Cross-checked |
| CAM-? | * * * | |
| CAM | [Sound of clicks - similar to sound of stabilizer trim actuation] | |
| 20.26:30.62 | RDO-2 | United five five three, an, ah Kedzie inbound |
| 20.26:35.97 | CAM-? | Flight |
| 20.26:36.38 | MTWR | United five five three, continue inbound, you're number two on the approach --'ll keep you advised. |
| 20.26:40.10 | CAM | [Sound of several clicks - similar to sound of electrical stabilizer trim actuation] |
| 20.26:40.47 | RDO-2 | Okay |
| 20.26:40.96 | CAM-2 | Cross-checked |
| CAM-3 | With a glideslope flag | |
| CAM-2 | No glideslope | |
| 20.26:41.10 | 9VS | Eh, nine VS has the runway |
| 20.26:43.06 | MTWR | Nine VS, runway three one left cleared to land |
| 20.26:44.67 | CAM-3 | Aaan the --- landing gear |
| 20.26:46.18 | 9VS | Okay |
| 20.26:48.40 | MTWR | Nine VS, do ya have the right runway in sight by any chance? |
| 20.26:50.41 | CAM-2 | Down, three greens |
| 20.26:51.37 | CAM-3 | Speed brake? |
| 20.26:51.37 | 9VS | Affirmative |
| 20.26:52.45 | CAM-2 | Ah --- armed |
| 20.26:52.6 | MTWR | 'ud you swing over to that and land? There's a jet about two m-- and disregard that, ah, okay, I see ya now, you'r cleared to land on thirty-one left |
| 20.26:54.69 | CAM | [Sound of click - similar to sound made by moving speed brake lever to armed position] |
| 20.26:56.04 | CAM-3 | Wing flaps |
| 20.26:58.75 | CAM | [Sound of click - similar to sound made by flap lever moving into detent] |
| 20.26:59.42 | CAM-2 | Thirty, green light, pressure fluid. |
| 20.27:01.48 | CAM-3 | An the auto-pilot? |
| CAM | [Sound of click - similar to electrical stabilizer trim actuation] | |
| 20.27:02.96 | CAM-2 | Disarmed |
| 20.27:04.11 | CAM-2 | Ah thousand feet |
| 20.27:04.50 | MTWR | United five fifty-three, execute a missed approach, make a left turn to a heading of --- one eight zero, climb to two thousand [between words 'of' and 'one' there is a pause and a voice in the background says 'one eighty'] |
| 20.27:05.74 | CAM | [Sound of stickshaker begins and continues to end of recording] |
| 20.27:07.56 | CAM-? | [Two to three hurried word at very low amplitude and masked by noise of stickshaker] |
| CAM | [Sound of click - similar to sound made by flap lever moving into detent] | |
| 20.27:12.14 | RDO-2 | Okay, left turn to one eight zero, --- left turn okay? |
| 20.27:13.88 | CAM-3 | Want more flaps? |
| 20.27:15.33 | CAM-? | Flaps fifteen. |
| 20.27:15.45 | MTWR | Yeah, make left turn to one eighty. |
| 20.27:16.14 | CAM-? | I'm sorry. |
| 20.27:16.47 | CAM | [Sound of click - similar to sound made by flap lever moving into detent] |
| 20.27:19.4 | CAM | [Sound of click - similar to sound made by landing gear lever moved out of detent] |
| 20.27:20.14 | CAM | [Sound of double click - similar to sound made by landing gear lever moved into up detent] |
| 20.27:10.64 | CAM | [Sound of landing gear warning horn begins and continues to end of recording] |
| 20.27:23.55 | CAM | [Sound of initial impact and garbled voice] |
| 20.27:24.46 | RDO-1 | [Sounds of impact and unintelligible voice] |
| 20.27:25.02 | RDO-1 | end of recording. |
