The private pilot and passenger were on a cross-country personal flight at 2,500 feet mean sea level and were about 15 miles north of their destination airport. They began the descent, and during the descent, the engine sputtered, followed by a total loss of power.
The pilot attempted to troubleshoot the loss of power, but was unsuccessful. However, he did not apply carburetor heat during the troubleshooting.
He then made a forced landing to a parking lot in Ferdinand, Indiana. During the landing roll, the airplane hit an embankment and nosed over. The pilot sustained serious injuries in the crash, while the passenger sustained minor injuries.
Post-accident examination of the airplane revealed that fuel was present in the fuel tanks and the fuel lines to the carburetor.
Examination revealed no evidence of any preimpact mechanical failures or malfunctions that would have precluded normal operation.
Weather conditions at the time of the accident were conducive to the accumulation of serious carburetor icing at glide power settings. It is likely that, during the descent, carburetor ice accumulated due to the pilot’s failure to apply carburetor heat, which resulted in the loss of engine power.
Probable cause: The pilot’s failure to apply carburetor heat in conditions conducive to the accumulation of carburetor icing, which resulted in a total loss of engine power.
NTSB Identification: CEN18TA233
This June 2018 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
Continental engine’s are more susceptible to carb. icing than Lycoming engine’s, especially the o-300 145 h.p. and the o-470 235 h.p. People flying these aircraft with these engine’s should be very aware of this condition on these type of engine’s. It’s the nature of the beast !!!
Carb ice usually gives more than a few hints and clues before it becomes debilitating. My C-90 (Continental) is an icemaker, especially in comfortably high humidity and temperatures around 60F. The heat loss in the carburetor throat brings that humid air to freezing, resulting in lost of rpm, just a little at a time.
My first experience with carb ice was almost 50 years ago during a morning practicing spins with my instructor (who was very uncomfortable doing spins – my way of subtle revenge). Recovery from the spin in a 150 is no big deal but when engine power was demanded there wasn’t any. Fortunately, the 150’s gear fit very nicely between the rows in a bean field and after walking to the farmer’s house to use his phone to call the FBO and back again the ice had thawed, the engine started and we flew it out again.
So they are speculating it was carb ice which probably could be. Doesn’t mention what type of aircraft it was. Certain airplanes are more prone to carb icing then others. I used to fly a 182 that could ice up on a hot summer day. If you pulled the full carb heat on with carb ice, the engine would quit immediately. You have to apply the car heat judiciously. Fly a 172 in the same meteorological conditions and there was no carb ice conditions at all. I’ve never been a proponent of full-on carb Heat unless you know how it affects your conditions at the time. Full carb Heat for a extended period at low RPM can load the engine up due to excessively Rich conditions. Push the power up – cough, ruff, low power.
Lycoming vs Continental engines there – Lycoming runs the intake pipes through the (hot) oil sump, and are thus less prone to carb ice.
The induction rubes are downstream from the carburetor. How does this prevent carb ice?
Induction tubes…
You’re right – I should have said the carb to bolted directly to the hot oil sump.
It was a Cessna 150F aircraft. Further information that I found showed a chart of probability of carb icing that placed the accident conditions squarely in the zone for Serious Icing under Glide Power which the engine was probably operating near given the descent. The pictures of the crash site would indicate the aircraft is a total write off, usable for parts scavenging only as the fuselage, wings and vertical tail all got badly crunched.
Very unfortunate. Similar to other accident reports where carb ice was suspected and the first memory item, in this case carb heat, was not applied. When engine roughness or loss of rpm occurs in carbureted models, the carb heat should immediately by applied.
I’m a pilot local to this area. The article doesn’t mention that the accident happened at night. Speculation of course, but had it been daytime, he might have seen the 5,000 foot runway 3-4 nm off his right wing. Hate to see an airplane get bent up for any reason, but glad they were both ok.
Not much info. on the conditions conducive to carb icing?