Boeing 727-222 accident near Denver, Colorado, May 31, 1984
On May 31, 1984 at about 7:34 pm local time, a Boeing 727-222, registered N7640U, was substantially damaged in an accident near Denver, Colorado (Stapleton airport). It was a flight of an unrecorded kind under scheduled airline rules (Part 121). No one was hurt; 105 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 31, 1984 · about 7:34 pm local time
- Place
- Denver, Colorado · Stapleton · map
- Type
- Accident
- Injuries
- No one was hurt; 105 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Boeing 727-222 · all 727-222s on the register
- Registration
- N7640U · registry record · serial 19913
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · scheduled airline rules (Part 121)
The NTSB's narrative final · quoted from the NTSB record
BEFORE TAKEOFF, THE CREW OF N7647U (UA FLT 663) NOTED CUMULUS CLOUDS & VIRGA IN THE AREA. AT 1327, A DEHAVILLAND DASH 7 CREW RPRTD A 25 KT LOSS OF AIRSPEED, BUT SVRL OTHER ACFT THEN TOOK OFF WITHOUT RPRTG A PROBLEM. DUE TO RADIO CONJESTION,THE CAPTAIN DID NOT QUERY OTHER AIRCREWS, BUT DECIDED TO CLIMB OUT AT V2 PLUS 20. WHEN THE CONTROLLER CLEARED FLT 663 FOR TAKEOFF, HE ADVISED THE CREW OF NUMEROUS WIND SHEARS IN 3 QUADRANTS, BUT USED INCORRECT TERMINOLOGY IN ISSUING THE WIND SHEAR ALERT. DURING TAKEOFF, THE ACFT STRUCK AN ILS LOCALIZER ANTENNA, 1074 FT FROM THE DEPT END OF THE RWY, & DAMAGED THE LOWER FUSELAGE. WHEN UNABLE TO PRESSURIZE THE ACFT, THE CREW RETURNED TO THE ARPT & LANDED. AN INVESTIGATIONREVEALED THE ACFT ENCOUNTERED WIND SHEAR FROM MICROBURST ACTIVITY WHICH REACHED ITS GREATEST ACTIVITY AS FLT 663 WAS TAKING OFF. THE WIND SHEARED FROM AN 8 KT HEADWIND TO 40 TO 56 KTS OVER A 44 SEC PERIOD. THE CREW NOTED A HESITATION WHILE ACCELERATING THRU 120 KTS, THEN AT OR BEYOND VR SPEED OF APRX 141 KTS, THE ACFT MOMENTARILY LOST 20 KTS.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Certificate: airline transport pilot, commercial pilot
- Ratings: multi-engine land; instrument: airplane
- Flight time: 12,400 hours in all; 8,000 in this make and model; 69 in the last 30 days
- Medical certificate: None (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Last inspection: continuous airworthiness programme; 0 hours since
- Maximum gross weight: 172,000 lb
- Seats: 144
- Landing gear: retractable
- Engine: P&W JT8D-7B (turbofan); 0 hours total
The flight
- Destination: LAS Las Vegas NV
- Flight plan: IFR
- Runway 35L, 11,500 ft by 150 ft
Weather at the time
- Light: daylight
- Visibility: 20 statute miles
- Sky: broken clouds at 8,000 ft; not recorded at 8,000 ft
- Temperature: 82°F (28°C), dew point 39°F (4°C)
- Altimeter: 29.00 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 7 | |||
| Passengers | 98 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.