N627WS

Destroyed
Fatal

Gates Learjet 25B S/N: 170

Accident Details

Date
Tuesday, January 13, 1998
NTSB Number
FTW98MA096
Location
HOUSTON, TX
Event ID
20001211X09446
Aircraft Damage
Destroyed
Highest Injury
Fatal
Fatalities
2
Serious Injuries
0
Minor Injuries
0
Uninjured
0
Total Aboard
2

Probable Cause and Findings

The flight crew's continued descent of the airplane below the glideslope and through the published decision height without visual contact with the runway environment. Also, when the captain encountered difficulty tracking the localizer course, his improper decision to continue the approach by transferring control to the first officer instead of executing a missed approach contributed to the cause. In addition, the following were factors to the accident: (1) American Corporate Aviation's failure to provide an airworthy airplane to the flight crew following maintenance, resulting in a false glideslope indication to the first officer; (2) the flight crew's failure to follow company crew coordination procedures, which called for approach briefings and altitude callouts; and (3) the lack of an FAA requirement for a ground proximity warning system on the airplane.

Aircraft Information

Registration
N627WS
Make
GATES LEARJET
Serial Number
170
Engine Type
Turbo-jet
Model / ICAO
25B LJ25
Aircraft Type
Fixed Wing Multi Engine
No. of Engines
2

Registered Owner (Historical)

Name
FIRST STAR INC
Address
3511 SILVERSIDE RD STE 105
Status
Deregistered
City
WILMINGTON
State / Zip Code
DE 19810-4902
Country
United States

Analysis

HISTORY OF FLIGHT

On January 13, 1998, about 0810 central standard time, a Gates Learjet 25B, N627WS, impacted terrain approximately 2 nautical miles (nm) east of the runway 26 threshold at George Bush Intercontinental Airport (IAH), Houston, Texas, during an instrument landing system (ILS) approach. (All times in this report are central standard time, based on a 24-hour clock.) The airplane was operated by American Corporate Aviation, Inc., of Houston and was registered to First Star, Inc., of Wilmington, Delaware. The positioning flight, which was operating under 14 Code of Federal Regulations (CFR) Part 91, had departed from Houston's Hobby Airport (HOU) about 0745 with a destination of IAH. The captain and first officer were the sole occupants aboard the flight. Instrument meteorological conditions prevailed for the flight, and an instrument flight rules (IFR) flight plan had been filed. Both flight crewmembers were killed, and the airplane was destroyed by impact forces and fire. Five people were waiting at IAH to board the airplane for a 14 CFR Part 135 charter flight to Fargo (FAR), North Dakota.

The airplane had been operated from Raytheon Aircraft Services, a fixed-base operator (FBO) at HOU, for about 1 month before the accident flight. Raytheon's records indicated that, on January 12, 1998, the Director of Operations for American Corporate Aviation verbally requested fuel for the airplane and that the wing and tip tanks were "topped off" with 372 gallons of jet fuel. During the afternoon of January 12, the captain of the accident flight taxied the airplane from Raytheon Aircraft Services to Fletcher Aviation, another FBO at HOU, and the airplane was placed in a hangar. About 1700, the director of operations and the captain removed a stretcher from the airplane and installed two passenger seats in its place. According to the director of operations, he discussed the next day's trip to Fargo with the captain and informed him who the first officer for the flight would be. The director of operations stated that he later observed the captain giving the first officer a preflight briefing.

The proposed round trip consisted of four flight segments: HOU to IAH, IAH to FAR, FAR to IAH, and IAH to HOU. According to the transcript of the telephone call, about 0528 on January 13, 1998, the captain called Montgomery County Automated Flight Service Station (CXO AFSS) and filed an instrument flight plan for a flight in N627WS from HOU to IAH and then from IAH to FAR. The proposed departure times from HOU and IAH were 0645 and 0800, respectively. When the briefer at CXO AFSS asked the captain if he could do anything else, the captain said, "yeah tell me how bad the weather is I know it is foggy as a son-of-a-gun." The captain was then given a weather briefing for the Houston and Fargo areas. The weather at IAH was reported as 1/4-mile visibility restricted by fog, vertical visibility of 100 feet, and temperature and dew point within 1 degree of each other. The forecast weather for FAR after 0900 called for unrestricted visibility and scattered clouds at 12,000 feet, becoming overcast at 10,000 feet between 1200 and 1400. The captain concluded the conversation about 0534 after saying, "well ok I'm just going to take my time and mosey on out to the airport after it gets a little better I'll get an update with you then we'll go."

While this briefing was being conducted, CXO AFSS received another telephone call about 0532 requesting a weather briefing for N627WS departing HOU at 0800 for a flight to IAH and then FAR. In an interview conducted during the accident investigation, the Chief Executive Officer (CEO) of American Corporate Aviation indicated that he placed this call to CXO AFSS. The CEO was told that the weather at HOU was calm winds, 1/8-mile visibility restricted by fog, an indefinite ceiling at zero feet, and both the temperature and dew point at 19 degrees Celsius (C). The weather at IAH was reported as calm winds, 1/4-mile visibility restricted by fog, an indefinite ceiling at 100 feet, and both the temperature and dew point at 17 degrees C. The call was concluded about 0540.

A line service technician employed by Fletcher Aviation stated that, when he arrived for work about 0605, the captain was already at the FBO. About 0612, the captain called CXO AFSS again, asking if the weather at IAH had gotten any better. He was told that the weather was reported as 3/4-mile visibility restricted by fog with an indefinite ceiling at 100 feet. CXO AFSS received a third call from the captain about 0646 requesting IAH weather. The captain was given a special weather report issued about 0606; the reported conditions included 1/4-mile visibility restricted by fog, light rain, indefinite ceiling at 100 feet, temperature and dew point within 1 degree, and occasional lightning in clouds from a thunderstorm to the south moving northeast. About 0706, CXO AFSS received a fourth call from the captain, asking if IAH weather had improved. The captain was told that the weather was reported as 1/4-mile visibility restricted by mist, an overcast ceiling at 100 feet, surface visibility of 4 miles, and a thunderstorm in the vicinity.

According to the Fletcher Aviation line service technician, the first officer arrived at the airport between 0645 and 0700. The airplane was then moved from inside the hangar to the ramp, and the technician connected a power cart to the airplane. At that time, the technician heard fuel being transferred to the fuselage fuel tank. The technician observed the first officer fill out a "trip log" form, which the technician faxed to American Corporate Aviation's "dispatch" office after the airplane taxied out. Safety Board investigators obtained a copy of this document from the CEO of American Corporate Aviation. The form was a copy of page 9.28 of American Corporate Aviation's Operations Manual, entitled "Dispatch Record." The form indicated that the route of flight would be HOU--IAH--FAR--IAH--HOU and that the IAH--FAR--IAH portion of the flight would be operated under 14 CFR Part 135.

According to cockpit voice recorder (CVR) data, the captain was the flying pilot on the flight from HOU to IAH, and the first officer was the nonflying pilot. After an uneventful takeoff from HOU, the first officer made initial contact with the IAH Terminal Radar Approach Control (TRACON) Departure North controller about 0746:21. The controller began vectoring the flight for an ILS approach to runway 26 at IAH and transmitted the following IAH automatic terminal information service (ATIS) weather conditions:

[information] Echo is current. wind is three four zero at seven.

visibility's one half, mist. ceiling is two hundred broken, six hundred

broken, nine hundred overcast. temperature one eight. our Humble

altimeter three zero, zero one. remarks, surface visibility is five.

runway two six RVR [runway visual range] is more than six thousand.

The Departure North controller then handed off the flight to the Arrival East controller. After a series of turns, the flight was cleared about 0751:43 for the approach to IAH and instructed to contact the IAH tower. The CVR recording does not indicate that the flight crew conducted a verbal approach briefing.

About 0752:51, the IAH Air Traffic Control Tower (ATCT) Local West controller cleared the flight to land on runway 26. Radar data indicated that the airplane began a descent from 2,000 feet mean sea level (msl) about 0753:17 from about 0.5 nm inside NIXIN (the final approach fix) on the left edge of the localizer course. The airplane descended to 1,600 feet msl, where it intercepted the center of the localizer course approximately 1.5 nm inside NIXIN. About 0753:47, the CVR recorded the captain stating, "I got a compass flag." Immediately after the captain's comment, the airplane departed the localizer centerline to the left, establishing a course about 25 degrees left of the final approach course. The airplane continued on this course for approximately 50 seconds and descended to about 700 feet msl.

According to CVR data, about 0754:36 the first officer said, "you wanna go missed and go back? it shows you right of course." The captain responded, "yeah yeah tell him we go missed." About 0754:41, the local controller said, "Lear uh, seven Whiskey Sierra uh, say heading." The first officer responded, "uh, we need to go missed.... we're going missed approach." A missed approach was then initiated from about 0.8 nm from the threshold of runway 27 on its extended centerline. (Runway 27 is south of and parallel to runway 26.) The flight was assigned an altitude and heading to fly and switched from local control back to approach control.

About 0756:05, the first officer told the controller, "we need to go back to Intercontinental or uh back to uh, Houston Hobby." The captain said to the first officer, "no, we just need to fly around a bit." The first officer then told the controller, "captain says, uh, we're gonna fly around if you can put us out uh, we're gonna try to straighten something out." The controller asked, "do you have a problem with the aircraft?" The first officer replied, "just the compass. we're working on it." According to CVR data, the captain and first officer spent the next few minutes attempting to clear the compass flag by resetting circuit breakers. The CVR recording provides no indication that the problem was resolved.

About 0759:10, the captain said, "well let's go back to Hobby, we can't, we can't do a trip like this," but then said, "well now let's think about this a second." The first officer asked the captain about the weather conditions in North Dakota. The captain replied that it was "severe clear" and then said, "uh, let's go on and try Intercontinental again." About 0759:42, the first officer requested another approach to IAH.

The controller began vectoring the fl...

Data Source

Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# FTW98MA096