Aerostar RALLY RX-8 accident near Morgan Hill, California, May 9, 1999
On May 9, 1999 at about 2:46 pm local time, a Aerostar RALLY RX-8 (balloon), registered N70290, was destroyed in an accident near Morgan Hill, California. It was a flight of an unrecorded kind under general aviation rules (Part 91). 2 people were killed and 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's selection of an inadequate takeoff site that did not allow sufficient horizontal clearance from obstacles in the takeoff path, and, his failure to ensure that all burners were connected to fuel sources, which reduced the available climb capability of the balloon. Also causal was the pilot's failure to activate the emergency vent panel and land prior to contact with the power lines, and, his use of an unapproved aluminum fuel tank, which ruptured during the power line contact and ignited a fire. A factor in the accident was the pilot's failure before takeoff to use pibals to quantify the wind speed.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 9, 1999 · about 2:46 pm local time
- Place
- Morgan Hill, California · map
- Type
- Accident
- Injuries
- 2 people were killed and 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Aerostar RALLY RX-8
- Registration
- N70290 · registry record · serial RX8-3214
- Damage
- Destroyed
- Flight
- Flight of an unrecorded kind · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
In the takeoff initial climb, the balloon contacted power lines, caught fire, and crashed into a field. The pilot setup the balloon for takeoff from a 798-foot-long open field, 298 feet upwind from 21,000-volt power lines. The FAA approved flight manual specifies that a horizontal distance of 100 feet for each 1-knot of wind speed be allowed between the takeoff point and any obstacle in the takeoff path. During the envelope inflation process, a 7- to 10-mph surface wind developed, which started dragging the basket toward the lines. The pilot elected to continue with the planned flight. He and the two fare-paying passengers took off and drifted into the power lines, which shorted and arced. An unapproved aluminum fuel tank in the basket ruptured and ignited the basket, envelope, and occupants. The pilot jumped from the basket and sustained serious injuries. The passengers remained in the basket and succumbed to thermal injuries. The balloon had been modified by the addition of an uncertified aluminum fuel tank to the two existing factory tanks that were composed of steel. During postaccident examination of the wreckage, a fuel line to one of the two burners was found not connected; with one burner inoperative, the balloon's climb capability was significantly reduced. The envelope's emergency deflation panel was found in the closed position and subsequent testing found it functional. According to the flight manual, the pilot's preflight actions should have included providing safety helmets to the passengers, ascertaining the winds aloft by launching a pibal, and ensuring that both burners were connected to fuel tanks and operational; none of the actions were completed. In addition, the pilot did not vent activate the envelope's emergency deflation panel to land when the collision with the power lines was eminent.
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: commercial pilot
- Ratings: rotorcraft: balloon
- Flight time: 133 hours in all; 12 in this make and model; 12 in the last 90 days; 12 in the last 30 days
- Medical certificate: Class 3 (expired)
- Seat: unk
The aircraft
- Airframe total time: 90 hours
- Last inspection: annual inspection, May 19, 1998; 14 hours since
- Maximum gross weight: 1,650 lb
- Seats: 0
- Landing gear: fixed
- Engine: (type not recorded); 0 hours total
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 310° at 5 knots
- Visibility: 20 statute miles
- Sky: scat at 25,000 ft
- Temperature: 50°F (10°C), dew point 43°F (6°C)
- Altimeter: 30.00 inHg
- Observation at 2:45 pm from RHV, 13 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 2 |
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.