8 December 1972 - United 553 The aircraft, named "City of Lincoln", took off from Washington-National Airport for flight UA553 to Chicago and Omaha. Departure time was 12.50 CST. Chicago ARTCC cleared the crew to descend to 4000ft and the flight was given vectors for a Midway Airport Runway 31L localizer course. At 14.19h the flight was transferred to Chicago Approach Control which later recquested UA553 to slow down to 180kts and later down to 160kts. After issueing a descent clearance down to 2000ft at 14.23h the controller requested the flight to slow down to approach speed because of separation between UA553 and a preceding Aero Commander. At 14.24h the Aero Commander passed the Outer Marker and was cleared to land on Runway 31L. Two minutes later UA553 passed the Outer Marker inbound. Then, at 14.27:04 the air traffic controller decided to issue a missed approach clearance: "United 553 execute a missed approach make a left turn to a heading of 180 climb to 2000". At the same time, having just reached 1000ft, the stick shaker suddenly activated. Full power was applied and the gear was retracted in an attempt to execute a missed approach. The Boeing continued to descend however, attaining a high nose up attitude (of at least 30deg, according to some survivors). The aircraft then clipped a tree and impacted trees, houses, utility pole cables and garages before coming to rest. Post crash fire destroyed part of the fuselage.
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
all times are in GMT
20.25:25.0 CHI APC 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. ----------------------------------------------------------------------------------------
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