NTSB CAROL · Event
Event CHI94LA130
Registry · N9187M
FAA Aircraft Registry record.
Make / Model
VAN'S AIRCRAFT RV-4
Year of manufacture
2001
Engine
LYCOMING 0-320 SERIES (180 hp)
Seats / Engines
2 seats · 1 engine
Last airworthiness date
20011005
ADS-B equipped
Yes — Mode-S ACB7BC
Registrant of record
PHILLIPS TIM
Source: FAA Aircraft Registry (releasable master file).
Aircraft involved
Probable cause & findings
FAILURE OF THE PILOT TO FOLLOW PROPER IFR PROCEDURES AND MAINTAIN PROPER ALTITUDE DURING THE APPROACH. FACTORS RELATED TO THE ACCIDENT WERE: DARKNESS, THE WEATHER CONDITIONS, AND FAILURE OF THE APPROACH CONTROLLER TO ISSUE AN IFR TRANSPONDER CODE TO THE AIRCRAFT WHEN HE PROVIDED THE IFR CLEARANCE, WHICH WOULD HAVE ALLOWED A LOW ALTITUDE ALERT TO BE TRIGGERED.
Factual narrative
HISTORY OF FLIGHT
On April 11, 1994, at 0603 central daylight time (cdt), a Cessna 182P, N9187M, registered to the Jerseyville Sport Flyers, of Jerseyville, Illinois, and piloted by an instrument rated private pilot, was destroyed during a collision with trees and terrain while flying the ILS approach for runway 08R at the Spirit of St. Louis Airport, Chesterfield, Missouri. Instrument meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 flight was operating on an IFR flight plan. The pilot received serious injuries. The flight departed Jerseyville, Illinois, at 0530 cdt. The pilot obtained a flight service station weather briefing for a flight from St. Louis, Missouri, to Cincinnati, Ohio, before departure. During his briefing the pilot was advised that thunderstorms and rain showers were approaching the St. Louis area from the west and southwest. He was also advised that the Spirit of St. Louis Airport's ILS glide slope was out of service for runway 08R. At the conclusion of the weather briefing the pilot filed an IFR flight plan from St. Louis, Missouri, to Cincinnati, Ohio. Two pilot rated friends of the accident pilot said the weather was about 700 overcast with four mile's visibility and light rain showers when he departed. The friends were asked if they were aware of the pilot's activities the day before the accident flight. They said he had attended a fish fry the day before and had left it about 2000 cdt. An interview with the pilot's wife confirmed this. She added that he retired for the evening about 2215 cdt, and awoke between 0330 and 0400 cdt on April 11, 1994. N9187M's pilot contacted the St. Louis approach control at 0533 cdt. He asked the approach controller for vectors to the Spirit of St. Louis Airport. The controller gave the pilot a VFR transponder code and told the pilot to maintain VFR at 2,500 feet. About three minutes later the controller asked the pilot "...are you going to be able to maintain VFR?" The pilot replied, "...just barely." After deciding that the pilot was instrument rated, the controller asked if he wanted an IFR clearance to the airport. The pilot responded that he would. At 0536 cdt, the controller stated: "Alright november eight seven mike cleared to Spirit Airport via radar vectors maintain two thousand five hundred." About nine minutes after receiving the IFR clearance, the controller asked if the pilot could see the airport. He added that if the pilot did not see the airport he would give the pilot "...vectors for an ILS eight right approach." N9187M's pilot repeated the controller's statement. About three minutes later, the controller asked the pilot if he could see the airport. The pilot stated he could not. The controller gave the pilot headings to intercept runway 08R's localizer. The controller gave the pilot his final localizer intercept heading, stating: "...maintain two thousand five hundred till established on the localizer cleared ILS eight right approach." The pilot was given weather information: "...St. Louis is measured ceiling niner hundred broken seventy-five hundred overcast visibility three rain fog and the altimeter is three zero-zero eight... ." N9187M's pilot responded by repeating his airplane's "N" number. After the pilot received the current weather, the controller asked him if he was turning onto the localizer. The pilot responded that he had not received the localizer signal. The approach controller contacted the Spirit of St. Louis air traffic control tower (ATCT) and asked, "Yeah hey uh your ILS is up right Kevin?" The tower controller said: "Yeah the localizer's up but I got here just a couple of minutes ago it was in alarm though so but uh. It was in alarm but the localizer is up now." The approach controller cleared N9187M's pilot for a second ILS approach. The controller asked the pilot if he was receiving the localizer and was told by the pilot that he was not. The approach controller called the ATCT and asked: "..does the localizer show in the green [?]." The tower controller confirmed it was showing in the green. The approach controller was told that the ceiling was 3,500 feet above the surface with a visibility of 10 miles in light rain showers. The pilot told the approach controller that he was receiving the localizer signal. A third approach clearance was issued, "Alrighty okay you're three miles from Snoop [the outer marker] cleared for ILS eight right approach november eight seven mike." At 0557 cdt the pilot repeated the clearance and was told to contact the tower. At 0600 cdt the tower controller told the approach controller, "We're open and advertising ILS to runway eight right." The approach controller was told that the automatic terminal information service (ATIS) letter identifier would be "...alpha." The approach controller asked the tower controller if N9187M's pilot had contacted them. The tower controller said the pilot had not contacted them. During the following 15 minutes the approach and tower controllers handled other aircraft and discussed the situation surrounding N9187M. They decided that the low altitude alert warning for N9187M did not activate because the airplane had been assigned a VFR transponder code.
PERSONNEL INFORMATION
According to the pilot's flying club records, he was administered an instrument competency check on May 5, 1993. At that time he reported he had a total time of 678 hours. The pilot's logbook was in the accident airplane and was not found after the airplane was retrieved. A conversation with the FAA's Springfield, Illinois, Flight Standards District Office Accident Prevention Program Manager (APPM) revealed the pilot had been active in the "Wings" program. The APPM said the pilot participated in numerous safety presentations established at his flying club.
WRECKAGE AND IMPACT INFORMATION
N9187M crashed onto the southeast corner of Howell Island. The island is located in the middle of the Missouri River, due west of the Spirit of St. Louis Airport. The airplane was positioned on the localizer course for runway 08R about 2.5 miles west of the airport. Based upon observation of a FAA Principal Operations Inspector (POI), N9187M's "...initial impact appeared to be the tops of 30 to 40 foot high trees west and approximately 1,000 feet from the crash site. The path of the aircraft from initial tree strike, appeared to be a controlled descent, clipping trees off at [a] constant descending rate." N9187M was not removed from the island because the island was flooded by the Missouri River for about two weeks. The POI said that N9187M's wreckage was contained within a 20-foot diameter area. The airplane was "...upside down, resting on the cockpit, with the tail pointed west. The wings were broken back but not totally separated from the fuselage." Rescue personnel observed fuel spilling from the airplane's wings. An on-scene examination of N9187M by the NTSB IIC revealed the following: The inside of attitude and heading indicators' rotor cases had scuffing on them. Both instruments' rotors were corroded and scuff marks were not observed. Scuff marks were found on the turn and slip indicator's rotor and case. The vacuum pump rotor rotated freely, its vanes were intact, and no dust was observed in the case. The altimeter showed 2,300 feet with a knollsman window setting of 29.71. Cockpit flood and post light rheostats were turned to full bright position. Strobe light switch was found 'ON' and the landing light switch was in the 'OFF' position. Both magnetos sparked when rotated on a test stand. When the propeller was moved by hand, the magneto drive gears and vacuum pump drive rotated. Rocker arms on the number three cylinder moved up and down during the propeller movement activity. Water was found in the carburetor float chamber and accelerator pump chambers.
ADDITIONAL INFORMATION
The pitot static test had been completed on December 12, 1992. N9187M was equipped with two VOR displays. The first VOR display unit (King KI209) had a glide slope indicator and was used for the ILS approach. The second VOR display unit had been set on a VOR frequency of 116.0 (Troy VORTAC). The first VOR's 'OFF' flag for the glide slope needle was located just above the needle's centered position. The 'OFF' flag window measures 3/32" X 5/16" with a white flag that had two red diagonal stripes on it. This unit was not an FAA technical standard order type and was not produced with the non-reflective glass. When the unit is not receiving a glide slope signal, its glide slope needle remains centered. Before working his position, the approach controller was given a relief briefing. His relief briefing consisted of being told of one airplane that was being worked, the list of briefing items was brought up on the radar display, and he recalled discussing the weather. He said that he was not briefed about the Spirit of St. Louis airport's runway 08R glide slope being out of service. The controller stated he knew that the Spirit of St. Louis Airport runway 08R glide slope was out of service, but the localizer was functioning normally. He recalled having issued glide slope out-of-service advisories in the past. He stated he had simply forgot to advise N9187M's pilot that the glide slope was out of service. He said he had "...no idea why I forgot." The controller said that when he cleared N9187M for the ILS it was the first ILS approach he issued to the Spirit of St. Louis Airport since the glide slope was out of service. The glide slope's outage was written on a wall board inside the ATCT's Tracon room. This wall message board was next to the Tracon's entrance/exit door. It was the controller's recall that the ILS outage was in the 'read and initial' binder. The binder was examined by the NTSB ATC group chairman, a notation regarding the ILS's glide slope outage was not found. A Notice To Airman (NOTAM) for the glide slope outage was issued on April 1, 1994, with a cancellation date of August 15, 1994. The tower controller stated he came to the facility at 0552 cdt. He stated he heard the ILS alarm when he opened the break room door. Upon looking at the ILS control panel he saw an illuminated green light associated with the ILS runway 08R. After resetting the alarm the tower controller said the light remained in the green. ILS alarms at the Spirit of St. Louis Airport occur more frequently in wet weather than dry weather according to the tower controller. A Nav-Com technician said that with the glide slope being out of service, the alarm could have been caused by either the localizer or outer compass locator. He said there have been no post accident complaints regarding the localizer operation. He said the glide slope equipment had been removed for runway construction. An examination of the Spirit of St. Louis Airport's ILS runway 08R approach plate revealed that an alternative altimeter setting was not stated in the event of one not being available from the airport's ATCT. The FAA's Air Traffic Controller's Handbook, FAA publication number 7110.65H, states that an aircraft conducting an ILS approach when the glide slope is reported out of service "...shall be advised at the time an approach clearance is issued." The pilot was contacted via telephone for an interview. Due to injuries received from the accident he was unable to remember any circumstances surrounding the accident. BEFORE FLIGHT, THE PILOT WAS TOLD THE ILS GLIDESLOPE FOR RUNWAY 8R AT THE DESTINATION (SUS) WAS OUT OF SERVICE. DURING A NIGHT ARRIVAL, THE APPROACH CONTROLLER (APCH CTLR) ASKED IF HE WANTED AN IFR CLEARANCE; HE SAID HE DID. THE CTLR PROVIDED VECTORS FOR AN ILS 8 RIGHT APCH, BUT CLEARED THE PILOT FOR THE APCH WITHOUT ADVISING THAT THE GLIDESLOPE WAS OUT OF SERVICE. ALSO, THE CTLR DID NOT ASSIGN AN IFR CODE, SO THE LOW ALTITUDE ALERT SYSTEM WAS NOT ACTIVATED. THE PILOT FLEW THRU THE LOCALIZER (LOC) COURSE, THEN SAID HE WAS NOT RECEIVING THE LOC. THE APCH CTLR ASKED THE TOWER IF THE LOC WAS OPERATIONAL & WAS TOLD 'IT WAS IN ALARM BUT THE LOCALIZER IS UP NOW.' THE PILOT WAS REVECTORED FOR THE APCH, THEN SAID HE WAS RECEIVING THE LOC. HE WAS CLEARED AGAIN FOR THE ILS. DURING THE APCH, N9187M DESCENDED BELOW THE LOC-ONLY MINIMUM DESCENT ALTITUDE (1020') & ILS DECISION HEIGHT (662'). SUBSEQUENTLY, THE AIRPLANE HIT TREES ON AN ISLAND IN A RIVER, 2.5 MI WEST OF THE AIRPORT. THE RIVER WAS BELOW THE AIRPORT ELEVATION OF 463'. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_1994_CHI94LA130.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
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