Carburetor Ice

1
Carburetor Ice

• The Insidious Killer
• Presented by
• Aerospace Services International, Inc.
• Navy Flying Club Managers Workshop, 1999

2
Agenda

• The Killer
• How does it happen?
• Observations
• Detecting Ice
• Carb Heat on Takeoff?
• Just be SAFE!!

3
The Killer!

• Carburetor ice is an insidious killer that
  appears without warning, often when least
  expected.
• Because it can form and ambush a pilot
  unexpectedly, we must exercise prudence when
  dealing with Carburetor Ice.

4
How Does it Happen?

• Carburetor creates a fuel/air mixture.
• Air is forced through a narrow opening in the
  intake, called a venturi.
• Air and fuel is mixed and a volatile mixture is
  created.

• Side effect of this reduction in pressure is a
  concurrent reduction in temperature.
• Moisture below freezing temperature
• Carburetor Ice (The Killer)

5
Carb Icing Probability Chart
6
Observations

• Weird Stuff
• Cessna 150/172 Skyhawks
• Piper Cherokee
• Beechcraft
• Carburetor Heat
• Meant to prevent the formation of ice, not to
  remove it.

7
Detecting Ice

• Is there anything we can do or is it a fact of
  life we have to live with?
• Carburetor Air Temperature Gauge
• Iceman Probe

8
Two Instruments Available

• Carburetor Air Temperature Gauge.
• Operates by placing a probe in the venturi and
  measuring the temperature at that point in the
  intake.
• (This is where ice will form if it going to.)

• Iceman Probe.
• Unlike the Carb. Temp Gauge, the Iceman Probe is
  said to alert the pilot to the actual formation
  of ice itself. It is designed to actually detect
  ice as it begins to form in the venturi tube of
  the carburetor.

9
Carb Heat

• The only thing that can reduce or prevent carb
  ice, is the application of carb heat early and
  often. If your Aircraft is not equipped with
  detection instruments, apply carb heat if you
  have the slightest suspicion that conditions may
  be conducive to ice forming in the carburetor.

10
Carb Heat on Takeoff?

• Students are told not to do so.
• Unless a pilot is required to get out of a short
  strip with an obstacle at the end of the runway,
  a slight loss of power wont substantially
  detract from the aircraft ability to take off and
  climb. Leaning the mixture will compensate for
  the slight loss of power.

11
Just be Safe!!

• No matter what your experience level, always be
  aware of the possibility of Carburetor Ice.
  Students and Instructors should make sure carb
  heat is applied when simulating a forced landing
  due to engine failure.

12
Conclusion

• Proper pre-flight planning can keep you from
  experiencing carb ice.
• Use the chart and you wont be surprised.
• FLY SAFE!