Rough Climb Over the Bay
Carburetor ice in a Piper Cherokee 180, low altitude, and water ahead — seconds matter
The scenario
Departing Albert Whitted Airport (KSPG), St. Petersburg, FL — Runway 07, climbing out on a 062° heading. Elevation 7 ft MSL; the runway is essentially at sea level. You are a Private pilot, roughly 250 hours total, current and proficient in the Piper Cherokee 180.
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 conditions are conducive to carburetor icing even though the temperature is well above freezing.
You are 380 ft AGL, climbing through 74 KIAS (Vy, best rate of climb), heading 062°, when the engine begins to run rough. Power is noticeably down — the tachometer is dropping. The water of Tampa Bay fills the windscreen ahead. KSPG's tower is part-time (0700–2100) and is open; you are in Class D airspace.
Aircraft: Piper Cherokee 180, solo, fuel tanks balanced (left and right tanks roughly equal), within limits. Carbureted Lycoming O-360-A, fixed-pitch prop, steam panel, fuel selector on RIGHT (you switched to RIGHT after takeoff to balance fuel burn). Nothing was written up; the airplane was airworthy at departure.
Pilot: you — a Private pilot, current, roughly 250 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 focused on the heading.
- {'label': 'Field', 'value': 'KSPG · Albert Whitted'}
- {'label': 'Runways', 'value': '7/25 · 18/36'}
- {'label': 'Elevation', 'value': '7 ft'}
- {'label': 'Aircraft', 'value': 'PA-28-180'}
- {'label': 'Dominant phase', 'value': 'Landing / Takeoff'}
The decision
Before we get into the decision tree — what do you already know about carburetor ice in the PA-28-180? (Pick all that apply; this records your baseline.)
What the record shows
What the NTSB files show
NTSB DEN07CA035 (2006): A Piper PA-28-180 on a personal flight lost engine power on base leg due to carburetor icing. The pilot attempted a forced landing on a road, swerved to avoid car lights, and struck a tree, resulting in substantial damage. The probable cause was carburetor ice formation in conditions conducive to serious icing, with contributing factors including unsuitable terrain and the tree obstacle.
NTSB ATL03LA148 (2003): A Piper PA-28-180 on a personal flight experienced engine power loss during takeoff climb after extended ground operation in conditions favorable for carburetor icing. The probable cause was the pilot's failure to apply carburetor heat prior to takeoff, allowing ice to form in the induction system.
NTSB NYC02FA025 (2001, fatal): A Piper PA-28-180 on a personal cross-country flight experienced engine failure due to carburetor icing and made a forced landing into trees near Mansfield, Ohio in darkness. The accident resulted from improper carburetor heat management and pilot impairment from antihistamine use, with contributing factors including night conditions and carburetor icing conditions.
The local environment at KSPG makes this scenario particularly unforgiving: Runway 07's departure end is open water — Tampa Bay. An engine failure on the Runway 07 departure at low altitude is a ditching, not a field landing. There is no open field, no road, no park. The water is the off-field environment. This is not hypothetical; it is the NLCD ground cover off that runway end.
The real accidents cited above occurred at other airports and in other aircraft — NOT at Albert Whitted Airport. KSPG has its own accident history (see field dominant patterns: LOSS_OF_CONTROL_INFLIGHT 20.0%, FORCED_LANDING 16.4%, DITCHING 12.7%), but these specific NTSB events happened elsewhere. The scenario is localized to KSPG 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 PA-28-180 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.
Key lesson — In warm, moist Gulf Coast air, the PA-28-180's carbureted O-360-A can accumulate serious carburetor ice even at cruise power and above-freezing temperatures. Apply full carburetor heat at the first sign of engine roughness or unexplained RPM loss. At low altitude over water, the decision window is measured in seconds — not minutes. Off Runway 07 at KSPG, the off-field environment is Tampa Bay: a delayed response means a ditching, not a field landing. Remember: the PA-28-180 fuel selector is LEFT / RIGHT with no BOTH position — you must actively manage tank selection to avoid starvation, but in this scenario, the problem is carburetor icing, not fuel starvation.
Debrief — teaching points
Carburetor ice forms in conditions you would not expect.
The FAA icing probability chart shows 'serious icing at glide power' at temperatures between roughly 20°C and 30°C when relative humidity is high — exactly the Gulf Coast afternoon conditions at KSPG. You do not need visible ice, freezing temperatures, or IMC. Warm, moist air at reduced power is the classic carb-ice environment. The PA-28-180's Lycoming O-360-A is carbureted; it has no fuel injection. Carburetor heat is the only tool.
The first symptom is subtle — a dropping tachometer and engine roughness.
In a fixed-pitch airplane like the PA-28-180, carburetor ice first shows as engine roughness and an unexplained RPM decrease. There is no dramatic power cut. Pilots who are not actively monitoring the tachometer miss the early warning. By the time the roughness is obvious, significant ice has accumulated. Scan the tachometer as part of your regular instrument scan, especially in conducive conditions.
Apply full carburetor heat — not partial — and expect an initial RPM drop.
When you apply carb heat to an iced carburetor, the RPM will drop further before it rises. This is expected and normal: the heat is melting ice and the resulting water is briefly disrupting combustion. Do not remove carb heat when the RPM drops — that is the heat working. Hold it full on. The RPM will recover as the ice clears, typically within 15–30 seconds depending on ice accumulation. Partial carb heat can worsen the situation by partially melting ice into water ingestion without fully clearing the restriction.
At KSPG Runway 07, an engine failure on departure is a ditching.
The off-field environment off Runway 07's departure end (heading 062°) is open water — Tampa Bay. There is no alternate landing surface. If the engine quits on the Runway 07 departure and altitude is insufficient to return to the airport, the outcome is a ditching. This is not a worst-case scenario; it is the geographic reality. Best glide is 65 KIAS. Cabin door unlatched before water contact. Fuel selector OFF, mixture idle cutoff, master off just before impact. Flaps for slowest possible touchdown speed — impact energy rises with the square of touchdown speed, so the slowest possible speed matters most. Know this before you line up on Runway 07.
The PA-28-180 fuel selector is LEFT / RIGHT — no BOTH position. Manage it actively.
Unlike some aircraft, the PA-28-180 has no BOTH position on the fuel selector. You must actively switch between LEFT and RIGHT tanks to avoid starvation. In this scenario, the problem is carburetor icing, not fuel starvation — but tank management is still your responsibility. Know which tank you are on, monitor fuel quantity in each tank, and switch tanks regularly (typically every 15–20 minutes of flight) to maintain balance and avoid running a tank dry. A rough engine could be carb ice OR fuel starvation — always check the fuel selector first if you have not switched tanks recently.
Proactive carb heat use in conducive conditions is not optional.
The PA-28-180 POH and the FAA Pilot's Handbook of Aeronautical Knowledge both recommend applying carburetor heat when conditions are conducive to icing — before the symptom appears. In a Gulf Coast summer departure, with OAT near 27°C and dew point near 21°C, that means applying carb heat during the run-up check (and confirming the expected RPM drop, then recovery) and considering its use during climb in visible moisture or high humidity. Waiting for the roughness to appear at 380 ft AGL over Tampa Bay is waiting too long.
Built from the real accident record
Scenario built from NTSB DEN07CA035 (2006 PA-28-180 carburetor ice / forced landing), ATL03LA148 (2003 PA-28-180 carb ice on takeoff climb), NYC02FA025 (2001 PA-28-180 carb ice / night forced landing), and localized to KSPG's real off-field environment.
NTSB reports: DEN07CA035 · ATL03LA148 · NYC02FA025
ACS tasks: PA.I.F — Weather Information · PA.I.G — Cross-Country Flight Planning · PA.IX.C — Emergency Approach and Landing · PA.I.H — Human Factors · PA.II.B — Engine Starting / Systems Preflight
Relevant FARs: §91.3 · §91.13 · §91.185
Step through the full decision tree, make the calls, and see where each choice leads — then debrief it with your CFI.
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