Hi Paul...
Some good information in that "Link".
WESTACH makes a good Carburetor Temperature Guage with a Low Temperature Alarm and Warning Light.
There are several good guages with alarms and warning lights available.
The DeHavilland DHC-2 Beaver and DHC-3 Otter both had Carburetor Temperature Guages with a Carburetor Temperature Control that could be set at different settings. Other notable aircraft like the Douglas DC3/Dak and Consolidated Canso also had similar systems. This was nothing like you see in your Cessna 150 or 172.
I am sure when aircraft went through instrument upgrades the Carburetor Temperature Guage was also replace with one that included a Low Temperature Alarm and Warning Light. I know some of ours did along with a GPS unit etc.
How to Fly Safely in Carb Ice Conditions
When icing conditions exist, apply carburetor heat often at your cruise throttle setting.
Never use partial carburetor heat unless the aircraft is equipped with a carburetor temperature gauge, ice light, or similar instrumentation. Partial heat can possibly make matters worse, unless you know exact carburetor temperatures. Remember, full heat or nothing.
When below the green band on the rpm or MP gauge, apply carburetor heat. It is good practice to use it on any descent where you have reduced power. Use that carburetor heat control on any aircraft at reduced power settings and especially for landing.
In conditions conducive to icing or if ice was noted during engine run-up, perform another carburetor heat check immediately before takeoff. DO NOT leave carburetor heat on for the actual takeoff. Check your POH or aircraft manual for general guidance.
Final Reminder
Carburetor heat will keep carb ice from forming if applied early enough, often enough, and long enough.
Final Note
The last Royal Canadian Air Force Dakota Aircraft lost in service was lost at too low an altitude to recover with full loss of crew while on a Search and Rescue Mission. The cause of the accident was Carburetor Ice.
On a personal note I was flying a Douglas DC3 with only the co-pilot south down Hudson Bay at about 8000 feet when we dam near lost an engine due to Carburetor Ice and our inattentiveness. The aircraft rolled ninety degrees before either one of us could get our feet on the rudder pedals. It happened in a split second.
We were lucky, very lucky, we had altitude and I had a co-pilot who was built like a wrestler. We were empty of freight and passengers.
Did I learn anything...oh yes.
Up to then we used to let the crewmen, loadies (whether they had a pilots licence or not) sit up front and fly when we had no passengers or freight and we would sit in the comfortable rear seat.
That came to an end, one pilot always had to be in the left or right seat all the time were my rules.
Sometimes it takes sticky pants to smarten some of us aviators up...
Sorry Paul do not know how to post a "Link", you know that red line most of you post to an information site. Have not figured that out yet.
Cheers...Happy Landings...Doug
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