Gates Learjet CORP. 35A accident near Springfield, Illinois, January 6, 2011
On January 6, 2011 at about 5:00 pm local time, a Gates Learjet CORP. 35A, registered N800GP, was substantially damaged in an accident during approach (IFR final approach) near Springfield, Illinois (Abraham Lincoln Capital airport). It was flown under charter and air-taxi rules (Part 135). 2 people had minor injuries; 4 others were unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot’s decision to conduct an instrument approach in icing conditions without the anti-ice system activated, contrary to the airplane flight manual guidance, which resulted in an inadvertent aerodynamic stall due to an in-flight accumulation of airframe icing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- January 6, 2011 · about 5:00 pm local time
- Place
- Springfield, Illinois · Abraham Lincoln Capital · map
- Type
- Accident
- Injuries
- 2 people had minor injuries; 4 others were unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Gates Learjet CORP. 35A
- Registration
- N800GP · no longer on the register · serial 158
- Damage
- Substantial damage
- Flight
- Flight · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
The flight encountered light rime icing during an instrument approach to the destination airport. The copilot was the pilot flying at the time of the accident. He reported that the airframe anti-icing system was turned off upon intercepting the instrument approach glide slope, which was shortly before the airplane descended below the cloud layer. He recalled observing light frost on the outboard wing and tip tank during the approach. The stick shaker activated on short final, and the airplane impacted left of the runway centerline before it ultimately departed the right side of the runway pavement and crossed a slight rise before coming to rest in the grass. The cockpit voice recorder transcript indicated that the pilots were operating in icing conditions without the wing anti-ice system activated for about 4 1/2 minutes prior to activation of the stick shaker. A postaccident examination of the airplane did not reveal any anomalies consistent with a preimpact failure of the flight control system or a loss of anti-ice system functionality. A performance study determined that the airplane’s airspeed during the final 30 seconds of the flight was about 114 knots and that the angle of attack ultimately met the stick shaker threshold. The expected stall speed for the airplane was about 93 knots. The airplane flight manual stated that anti-ice systems should be turned on prior to operation in icing conditions during normal operations. The manual warned that even small accumulations of ice on the wing leading edge can cause an aerodynamic stall prior to activation of the stick shaker and/or stick pusher.
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
What happened, in order
- Structural icing during approach (IFR initial approach)
- Aerodynamic stall/spin during approach (IFR final approach) defining event
- Hard landing during landing (flare/touchdown)
- Runway excursion during landing (flare/touchdown)
- Landing gear collapse during landing
The NTSB's findings
- Environmental issues › Physical environment › Object/animal/substance › Snow/ice › Contributed to outcome
- cause Personnel issues › Task performance › Use of equip/info › Use of manual › Pilot
- cause Environmental issues › Conditions/weather/phenomena › Temp/humidity/pressure › Conducive to structural icing › Decision related to condition
- cause Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Pilot
Pilot
- Certificate: airline transport pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 5,932 hours in all; 827 in this make and model; 2,208 as pilot in command
- Last flight review: October 28, 2010
- Medical certificate: Class 1 (without waivers/limitations)
- Seat: rgt
- Injury: minor injuries
Co-pilot
- Certificate: airline transport pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 1,657 hours in all; 802 in this make and model; 755 as pilot in command
- Last flight review: May 24, 2010
- Medical certificate: Class 1 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 16,321.4 hours
- Last inspection: continuous airworthiness programme, June 21, 2010
- Maximum gross weight: 18,300 lb
- Seats: 10
- Landing gear: retractable
- Engine 1: Garrett TFE 731 SER (turbofan); 0 hours total
- Engine 2: Garrett TFE 731 SER (turbofan); 0 hours total
- Fire on the ground
- Operator: Priester Aviation LLC
The flight
- Departed from: MDW Chicago IL at 4:34 pm
- Destination: SPI Springfield IL
- Flight plan: IFR
- Runway 22, 8,001 ft by 150 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 300° at 14 knots, gusting 19
- Visibility: 10 statute miles
- Sky: overcast at 1,600 ft
- Temperature: 28°F (-2°C), dew point 21°F (-6°C)
- Altimeter: 29.78 inHg
- Observation at 4:52 pm from SPI, 1 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | 1 | ||
| Passengers | 1 | 3 |
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.