Rough Climb Over Tampa Bay

Departing Peter O Knight Airport (KTPF), Tampa, FL — Runway 04, climbing out on a 037° heading. Elevation 8 ft MSL; the runway is essentially at sea level. This is a non-towered field (CTAF 122.8); you are in Class G airspace below 1,200 ft MSL, overlain by Tampa Class B above that altitude.

It is a hazy Florida afternoon in late spring: OAT 27°C, dew point 21°C, altimeter 29.92. Scattered clouds at 2,500 ft, light rain shower two miles to the northeast. Visibility 8 SM. Classic Gulf Coast conditions — warm, moist, and exactly the environment the FAA icing probability chart marks as 'serious icing at glide power, moderate icing at cruise power.' The relative humidity is 72%.

You are 350 ft AGL, climbing through 68 KIAS (Vy, best rate of climb for the C150M at sea level), heading 037°, when the engine begins to run rough. Power is noticeably down — the tachometer is dropping. The water of Tampa Bay and Hillsborough Bay fills the windscreen ahead. Off Runway 04's climb-out end, the off-field environment is dense development, medium development, and low-density development — not ideal, but land is there. Off Runway 22 (the reciprocal), the environment is open water — a ditching.

Aircraft: Cessna 150M, solo, full fuel (18 gallons usable), within limits. Carbureted Continental O-200-A, 100 hp, fixed-pitch prop, steam panel, fuel selector on BOTH. Nothing was written up; the airplane was airworthy at departure. The C150 is marginal on climb at gross weight in heat and high density altitude; you are at the edge of performance.

Pilot: you — a Private pilot, current, roughly 180 hours total. You did not apply carburetor heat during the run-up because the engine ran smoothly. You did not apply it after takeoff because you were heads-down on the climb and the engine sounded normal at first.

NTSB ERA25LA028 (2024): A Cessna 150H encountered carburetor ice at cruise altitude in conditions with 100% relative humidity. The engine ran rough and lost power. The probable cause was carburetor ice formation in conditions conducive to serious icing, with insufficient time and altitude for carburetor heat to clear the accumulated ice. The pilot had not applied carburetor heat proactively in conditions that clearly warranted it.

NTSB ANC25LA005 (2024): A Cessna 150 on a personal flight experienced partial engine power loss due to carburetor ice during initial climb in conditions with 70% relative humidity conducive to serious icing at glide power. The pilot applied carburetor heat but did so improperly — partial heat rather than full on — which worsened the situation. The probable cause was improper use of carburetor heat while operating on Mogas in icing conditions.

NTSB ERA24LA087 (2024): A Cessna 150M on a solo cross-country instructional flight experienced partial engine power loss due to carburetor icing when the student pilot failed to apply carburetor heat. The pilot made a diversionary landing but failed to attain a proper touchdown point, resulting in a runway excursion. The probable cause was the pilot's failure to use carburetor heat in icing conditions.

NTSB CEN21LA381 (2021): A Cessna 150M experienced partial engine power loss due to carburetor icing during takeoff near Wadsworth, Ohio, when the pilot failed to apply carburetor heat despite conditions in the moderate-to-serious icing range. The pilot made a forced landing to a corn field where the aircraft nosed over. The pilot survived.

NTSB CEN23FA401 (2023, FATAL): A Cessna 150K on an instructional flight practicing touch-and-go landings experienced partial engine power loss due to fuel system blockage and subsequently stalled during a descending left turn at low altitude. The flight instructor failed to maintain adequate airspeed after the power loss, and the airplane exceeded its critical angle of attack and entered an aerodynamic stall. The accident was fatal.

NTSB CEN23FA077 (2023, FATAL): A Cessna 150H on an instructional flight conducted a night visual approach to a non-towered airport in dark conditions with no cultural lighting. The aircraft descended below safe altitude and impacted a farm field 1.2 miles short of the runway. The probable cause was loss of engine power due to carburetor icing and the flight instructor's failure to apply carburetor heat and maintain control during the forced landing in dark night conditions. The accident was fatal.

The real accidents cited above occurred at other airports and in other regions — NOT at Peter O Knight Airport. KTPF has its own accident history (see field dominant patterns: FORCED_LANDING 19.4%, LOSS_OF_CONTROL_INFLIGHT 16.7%, DITCHING 11.1%), but these specific events happened elsewhere. The scenario is localized to KTPF to make the off-field environment real and consequential for you as a student here.

The consistent thread across all these events: carburetor ice in the C150 is insidious. It builds gradually, the first symptom is roughness and a dropping tachometer (not a dramatic power cut), and by the time it is obvious, it may be too late for a comfortable recovery. The fix — full carburetor heat, immediately, at the first sign of roughness in conducive conditions — is simple. The failure is always a delay.