Emcott12 0 Posted August 19, 2009 Share Posted August 19, 2009 The thing that I have discovered over and over again, is that I have absolutely flawless flights for hours, but the minute I encounter any rain and I'm not talking freezing rain the engine issues begin. I watch the carb temps fall and no matter how much I play with either carb heat or manifold, the same results will occur, crash and burn. I can be on a 2 hour flight and if rain is in the mix forget it. Great plane but there has to be some kind of a bug here. Take a flight and encounter rain and you will see the effect is in short order. That's why the engine issues were so bad in the mission, if you noticed you did'nt begin to have issues till you encountered rain. If I'm wrong about this, great and tell me what I'm doin wrong. It was what was occuring in the mission that made me want to see what effect rain would have on a flight that was uneventful. Sputter, sputter, loss of power, minor recovery, clank, clank, engines seize. Link to comment Share on other sites More sharing options...
Finn 873 Posted August 19, 2009 Share Posted August 19, 2009 You should apply Carburetor heat.. But the Carburetor heat switches are NOT simple On/Off switches, but Open/closes dampers wich directs more or less of the inlet air through the heaters. If Carburetor air temperature drops below 26°C and there is moisture in the air, open the Carburetor heaters by setting the heater switches to the "Hot" position, but be ready to switch them back to "Off" before reaching 50°C, preferable stop when reaching 34°C. Also note that Carburetor heating is depending on throttle setting, since the inlet air is heated by the exhaust stacks. So when You start to retard the throttle for the descend, monitor Carburetor air temp and adjust the heaters accordingly. When Carburetor air temperature goes beyond 50°C You will start to loose power. Finn Link to comment Share on other sites More sharing options...
Emcott12 0 Posted August 19, 2009 Author Share Posted August 19, 2009 Thanks for reply Finn, It just seems too strange that this aircraft can operate flawless till rain and not a cold rain at that is introduced and can have such an effect as to the point of bring the aircraft down. Every flight goes off without a hitch, but add rain to the event and within seconds the engines are in trouble and are unable to recover. But thanks very much for time in responding. Link to comment Share on other sites More sharing options...
Finn 873 Posted August 19, 2009 Share Posted August 19, 2009 If You keep Carb air temperature bewteen 30 and 50°C this should really not happen. Finn Link to comment Share on other sites More sharing options...
vgbaron 2 Posted August 19, 2009 Share Posted August 19, 2009 Thanks for reply Finn, It just seems too strange that this aircraft can operate flawless till rain and not a cold rain at that is introduced and can have such an effect as to the point of bring the aircraft down. Every flight goes off without a hitch, but add rain to the event and within seconds the engines are in trouble and are unable to recover. But thanks very much for time in responding. PMFJI but there were a lot of old a/c that I flew in real life (not the Cat) that were just as sensitive to certain conditions. It was drummed into me to be very aware of the carb heat under certain conditions or pay the consequences. As Finn said, one of the most dangerous times in when throttles are retarded for approach and landing. Learn to stay ahead of the curve with the carb heat and you'll have no problems, get behind and you'll probably crash - just like real life except in FSX you get to walk away. Vic Link to comment Share on other sites More sharing options...
Emcott12 0 Posted August 19, 2009 Author Share Posted August 19, 2009 Here's the thing though. When rain is encountered, by me anyway, the carb heat drops so rapidly that its crazy, power loss begins. Then I switch on carb heat which rapidly rises the heat and I begin a minor recovery, but thats lost within seconds as the carb heat soars to the point of power loss. Then, I attempt to switch the carb heat off, as I'm losing all power once again, but this does nothing and the aircraft over and over again is unable to recover. This occurs over a matter of a minute if not seconds. Its totally unmanageable. I suggest to you as well as Finn, take a flight and introduce rain and watch the fun begin. I have not been able to complete one single flight when rain is introduced with this aircraft. I've been flying for quite a few years now in real life and I'm almost 60 and have never experienced these issues in the way that this aircraft responds. Link to comment Share on other sites More sharing options...
Emcott12 0 Posted August 19, 2009 Author Share Posted August 19, 2009 I finally manged to complete a flight in the rain, but I must say the constant switching of the carb heaters is a real chore. From heat to cold and switching to the off position is a constant issue, for me anyway. I keep monitoring temps and eventually get a grip on the temp somewhat. This can't possibly be accurate. A pilot would go nuts with this. If this was an icing issue I could understand, but warm rain. Well, I have never flown the Cat in real life and if this is the case and they dealt with this constant crazy temp issue, then my hat is off to them. On another note, without a doubt Aerosoft is one of the finest software companies and I have enjoyed so very much the things they've offered. Link to comment Share on other sites More sharing options...
vgbaron 2 Posted August 19, 2009 Share Posted August 19, 2009 Hmm - I'll leave the technical answers to the developers but I've had several flights in the rain in the Cat and have not experienced what you describe. Yes, the temps rise and fall but no where near as rapidly as you. Vic Link to comment Share on other sites More sharing options...
Finn 873 Posted August 20, 2009 Share Posted August 20, 2009 Emcott12... I will take a closer look on this ASAP... But You said that temperature drop was very fast ! This sounds as if You are using real weather. Either weather supplied by FSX own real weather or a weather program like ASX / ASA. There has been and still might be an issue with suddently changing temperatures and windshifts, wich isn´t realistic, using these programs. Carb icing conditions in the catalina is determined like this: If Carb air temp is 0<= Carb air temp <= 26°C and There is moisture in the air. Determing moisture is done either when You are inside a cloud or below a certain visiblity level. Low visiblity is most often caused by high humidity. Presence of rain is not used for this type of carb icing simulation, because if the weather is setup realistic, visiblity will be low when raining. The other instance of carb icing occurs when rain is present and ÷15<= Carb air temp <= 0°C. Thats when we determine that freezing rain is present. Bottom line again is that as long as You keep carb air temp above 26°C (32° is better) carb icing will not occur. If outside temperature is dropping very fast, then it´s not caused by the Catalina, but from the weather source, be it FSX own real weather or an external weather program. I´m not saying that there isn´t an issue with our carb icing script, but we cannot make a realistic carb icing script that works if the weather doesn´t behave realistic. Beeing a real pilot I also asume that You check enroute weather conditions before take off, and thus is prepared for any hazardous weather You might encounter. I will try out a flight starting in dry conditions, then fly into rain and closely watch what happens. Finn Link to comment Share on other sites More sharing options...
Emcott12 0 Posted August 20, 2009 Author Share Posted August 20, 2009 Thanks for looking into it Finn. Link to comment Share on other sites More sharing options...
Finn 873 Posted August 21, 2009 Share Posted August 21, 2009 Today I looked into Yor reported issue. I started from an airport with the following conditions: Clouds few No rain 15°C Visiblity 20 mi I flew towards an area appr. 30 nm away, where I setup the following conditions: Broken clouds High rate of rain 8°C Visibility 5 mi Carburetor heat was off after take off and until meeting the rain. After about some 5-7 minuttes of flying I flew into the rain. Visibility and temperature dropped too as I had setup. After a short time my engines started to "act up" and loose power. I then turned Carburetor heat to HOT until appr. 30° Carburetor air temperature was reached, then setting them back to Off (remember it´s a 3 position switch COLD-OFF-HOT). Power was regained, and I could fly for at least 15 minuttes without any problems, before I ended my flight. Not necessary a prove, but I didn´t see any issues with flying into the rain. Best regards Finn Link to comment Share on other sites More sharing options...
Jigsaw 20 Posted August 24, 2009 Share Posted August 24, 2009 I can confirm that there is no issue in rain whatsoever. It seems to me that Emcott still doesn't realize that the carb heat isn't a simple on/off switch but a three position switch. So let me reiterate once more to be on the safe side: Up position: raises temperature Center position: freezes temperature at the current level (!!!) Down position: lowers temperature The ideal temperature range of the carb heat is between 32° and 50°. So, in order to apply carb heat properly you flip the switch to its Up position until the temperature reaches a point between 32° and 50°. Then, and this is imperative, you have to flip the switch to the Center position to maintain the current temperature. If you don't do that you push the heat past 50° and you also get a loss of power, this time because of too much heat. Again, just to make it absolutely clear: for a proper carb heat setting you have the center the carb heat switch at the desired temperature. You can't leave the carb heat switch in the HOT position like you can do in other aircraft with simple on/off switches. Also keep in mind that increasing/reducing throttle also changes the temperature of the carburetor. Link to comment Share on other sites More sharing options...
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