ERA23LA191

NTSB accident investigation · Cessna 152 · Danbury, CT · April 10, 2023

Accident · Minor injuriesClass 3 · LimitedFinal report
Date
April 10, 2023, 17:59 local (21:59 UTC)
Place
Danbury, CT
Injuries
2 minor
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N757YMCessna 152
Defining event
Approach: Fuel exhaustion
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Eastern Region Aviation
Parties
FAA/FSDO
FAA report
20230410003979A
Case key
107046

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

The flight instructor’s inadequate preflight fuel planning and oversight of the preflight inspection, which resulted in a total loss of engine power due to fuel exhaustion.

Findings · 3

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Fluids: fuelAircraft › Fluids/misc hardware · Fluid levelCessna 152: 26 casesAll aircraft: 1,695 casesProbable cause
Planning/preparation: fuel planningPersonnel issues › Task performance · Instructor/check pilotCessna 152: 13 casesAll aircraft: 719 casesProbable cause
Inspection: preflight inspectionPersonnel issues › Task performance · Instructor/check pilotCessna 152: 14 casesAll aircraft: 551 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The airplane was fueled earlier in the day then flown on 3 separate flights totaling 3.1 hours. Before the accident flight, the student pilot used a fuel dipstick to check the fuel level in each tank but she did not recall the fuel quantity in either tank and the flight instructor did not verify the fuel quantity. After departure, with a reported 15 gallons of fuel on board, the student performed pattern work, airwork, and more traffic pattern work. After the 3rd go-around, while on the downwind leg abeam the landing spot, the flight instructor took over the controls to demonstrate a landing. After turning onto base leg, the engine began to lose power. He pitched then nose down and reported the engine started and for about 2 seconds before losing power completely. He noted there were 2 high towers near the end of the runway and turned toward a grass field behind him and performed a steep spiral to lose altitude. The airplane slowed, and he heard the stall warning horn. He moved the flap selector from 10° to 20° then braced for impact. The airplane impacted a shed and came to rest adjacent to a house. Postaccident examination of the engine and its systems revealed no evidence of preimpact failure or malfunction. The airframe fuel strainer was found to contain about 1 ounce of fuel and the carburetor bowl was empty. The right wing contained about 1.7 gallons of fuel and the left fuel tank was empty. The usable fuel capacity of the airplane was 24.5 gallons. The airplane was flown 5.3 hours since the fuel tanks were last filled. The published fuel consumption rate for the engine was listed as being between 5.8 gallons per hour (gph) and 9.5 gph depending on power settings used. Given the fuel capacity of the airplane and the amount of time the airplane was flown after being fueled, it is likely that the loss of engine power was a result of fuel exhaustion.

Factual narrative

The airplane was modified in accordance with multiple Supplemental Type Certificates (STC’s) which included installation of a Lycoming O-235-L2C(M) engine and installation of a Sensenich fixed pitch propeller. The engine limitations section of the FAA Approved Airplane Flight Manual Supplement (AFMS) associated with the engine and propeller modifications stated that the rated rpm was 2,800 and 125 horsepower for all operations. The performance section of the AFMS specified that the incorporation of the STC into the airplane would result in increased fuel consumption relative to the values given in the airplane flight manual. According to the Airplane Type certificate Data Sheet, the total usable fuel capacity of the airplane was 24.5 gallons with an unusable fuel amount in each wing fuel tank of .75 gallon for a total unusable fuel capacity of 1.5 gallons. The Pilot’s Operating Handbook specified that the fuel consumed during engine start, taxi, and takeoff was 0.8 gallon. According to the engine Operator’s Manual, the fuel consumption in terms of gph varied from 9.5 gph at normal rated power to 5.8 gph at 65% rated power. According to fuel records, 16.6 gallons of 100 low lead fuel were added on the morning of the accident, filling the fuel tanks. Operator records showed that between the time the airplane was fueled and the accident flight, the airplane flew 3 flights totaling 3.1 hours. The elapsed time for the accident flight was 2.2 hours as documented by the hour meter. The airplane was flown for a total of 5.3 hours since it was last fueled. On April 10, 2023, about 1759 eastern daylight time, a Cessna 152, N757YM, was substantially damaged when it was involved in an accident near Danbury, Connecticut. The flight instructor and student pilot sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight. The student reported she performed weight and balance calculations, which reflected that there were 15 gallons of fuel on board. The flight instructor later reported he used a rate of 5 gallons-per-hour for fuel consumption calculations, or about 3 hours of fuel remaining, but that did not consider the fuel consumed for engine start, taxi, or takeoff. The student stated that she performed a preflight inspection that included a check of the fuel tanks using a dipstick, though she could not recall the value or reading in either tank. Her flight instructor indicated there was enough for the intended flight though he stated that he did not check the fuel tanks, and he could not recall either fuel gauge reading at engine start. The student performed an engine run-up before departure, which included a check of the magnetos and carburetor heat, both of which were operative. All instruments were working, and the flight instructor had her check the fuel gauges, but he did not recall her telling him anything about them. According to ADS-B data, the flight departed from runway 26 about 1601,and the flight instructor stated that after takeoff they remained in the airport traffic pattern and performed a go-around, and a normal landing. They departed the airport traffic pattern to practice airwork, then returned to the airport to do more pattern work. After the 3rd go-around, while on the downwind leg abeam the landing spot, he took over control of the airplane to demonstrate a landing and turned onto the base leg of the airport traffic pattern. While flying at 65 knots between 800 and 900 ft mean sea level, the engine began “sputtering.” He pitched down and reported the engine started and only ran for about 2 seconds, then it lost all power. He looked at runway 26, and noted there were 2 high towers near the end of the runway and remembered a grass field behind him and turned to fly towards it. He performed a steep spiral to lose altitude. The airplane slowed, and he heard the stall warning horn. He moved the flap selector from 10° to 20° and braced for impact. The student reported the airplane impacted a shed. Both pilots reported an EMT told them they smelled of fuel after the accident. According to the FAA inspector, the airplane impacted a residential area about 1 mile east of the Danbury Municipal Airport (DXR), Danbury, Connecticut. The right wing impacted near the roof line of a house adjacent to the shed, then impacted the shed. There was no postimpact fire. The airplane came to rest listing to the right. No fuel was drained from the left fuel tank which was nearly vertical and about 1.7 gallons were drained from the right fuel tank. Examination of the fuel system following recovery revealed broken fuel supply lines in the cockpit area; however, there was no blue stains in those areas. Although the fuel supply line to the airframe fuel strainer was kinked and the bowl was separated from the firewall the bowl was drained and found to contain about 40 milliliters, or about 1 ounce of fuel. The carburetor bowl did not contain any fuel. There were no discrepancies with either fuel cap which were vented. No discrepancies other than impact damage were noted to the fuel supply lines. Due to impact damage the fuel gauges were not electrically checked. Postaccident examination of the engine revealed no evidence of preimpact failure or malfunction of the powertrain, ignition, air induction, or exhaust systems. Throttle and mixture control continuity was confirmed from the cockpit to the carburetor. There were no nicks on the leading or trailing edges of either propeller blade and neither propeller blade exhibited scoring on the cambered side or blade face. One blade exhibited a slight aft bend.

Aircraft

Registration
N757YM
Reported as
Cessna 152 (NO SERIES EXISTS)
Category
Airplane
Serial number
15280110
Built
1977
Airframe hours
5,833.6
Engine
Lycoming O-235-L2C (M), 125 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Operator
Darcy Aviation LLC
Registered owner
Darcy Aviation LLC
Airworthiness certificate
Standard, Utility
Last inspection
100 hour · March 30, 2023 · 17 hours before
Departed
DXR · Danbury, CT
Flight plan
VFR
Airport
DXR · Danbury Municipal Airport
Equipment
Stall warning system, ADS-B

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew · 2

As NTSB recorded them. NTSB leaves out names.

Role
Student pilot
Age
18
Injuries
Minor
Seat
Left
Restraint
Lap only
Flight hours
8 total
Role
Flight instructor
Age
29
Injuries
Minor
Certificates
Flight instructor, Commercial
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, With waivers/limitations
Last flight review
February 14, 2022
Seat
Right
Restraint
Lap only
Flight hours
206 total · 15 in this make and model · 142 as pilot in command · 21 in the last 90 days · 18 in the last 30 days · 6 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Visibility
10 statute miles
Lowest ceiling
None
Temperature
66 °F, dew point 14 °F
Altimeter
30.30 inHg
Turbulence
Unknown
Observed at
KDXR, 1 nm away
METAR
KDXR 102153Z VRB05KT 10SM CLR 19/M10 A3030 RMK AO2 SLP262 T01891100

Docket · 15

The files NTSB released with the investigation on March 19, 2025, on NTSB’s docket system: statements, records, photos and specialists’ reports. 44.0 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.