Amateur-built Baby Belle accident near El Dara, Illinois, August 28, 2005
On August 28, 2005 at about 2:15 pm local time, a amateur-built Baby Belle (helicopter), registered N9094P, was destroyed in an accident near El Dara, Illinois. It was a personal flight under general aviation rules (Part 91). 1 person was killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The manufacturer failed to specify a relief radius on the tail rotor spindle drawings, which resulted in the spindle being manufactured with an inadequate relief radius at the point of fatigue failure.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 28, 2005 · about 2:15 pm local time
- Place
- El Dara, Illinois · map
- Type
- Accident
- Injuries
- 1 person was killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built Baby Belle
- Registration
- N9094P · no longer on the register · serial 2053
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The experimental amatueur-built helicopter collided with trees and terrain following an in-flight separation of a tail rotor blade. Witnesses reported seeing the helicopter spinning prior to it contacting the terrain. The helicopter was involved in a hard landing in 2004 after which the main rotor blades and tail rotor assembly including the spindle and blades were replaced. According to the pilot's friend, they balanced the new tail rotor blades after they were installed, but the blades continued to run "rough." The pilot voiced these concerns to the manufacturer and the manufacturer sent replacement tail rotor blades to the pilot. According to the manufacturer and the pilot's friend, the helicopter was running fine after the replacement blades were installed. Examination of the wreckage revealed all major components of the helicopter were located at the main wreckage site except for one of the tail rotor blades and the respective outboard 2 inches of the tail rotor spindle which were not located. The tail rotor spindle contained two integral rods, which extended out in opposite directions. The length of each rod was manufactured with sections of consecutively reduced diameter. A metallurgical examination of the spindle revealed a fatigue failure was present, which initiated at the fillet radius between the sections where the rod steps down from 0.812-inch diameter to 0.750-inch diameter. The relief radius in this area was rough and irregular. The manufacturer provided the engineering drawings for the tail rotor spindle. Drawing #15 did not specify a relief radius for the transition area between the .812-inch and .750-inch diameter sections. On September 14, 2005, Canadian Home Rotors (CHR), provided a revised drawing #15 requiring a 0.0156-inch relief radius between the 0.812-inch and 0.750-inch diameter sections. The relief radius measured at the failure was approximately 0.0073-inch.
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: private
- Ratings: rotorcraft: helicopter
- Flight time: 246 hours in all
- Last flight review: March 1, 2004
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: rgt
- Injury: fatal
The aircraft
- Maximum gross weight: 1,450 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-320 (piston); 0 hours total
- Fire on the ground
The flight
- Departed from: New Canton IL at 2:00 pm
- Destination: New Canton IL
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 230° at 4 knots
- Visibility: 10 statute miles
- Sky: a few clouds at 11,000 ft
- Temperature: 70°F (21°C), dew point 63°F (17°C)
- Altimeter: 29.88 inHg
- Observation at 1:54 pm from UIN, 22 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
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.
Other NTSB records under N9094P the same tail number, which may have belonged to a different aircraft at the time
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.