The A2A Simulations Community

I am running Windows 7 Ultimate 64-bit SP1, all updates installed.

FSX WITH Acceleration, COTS v1.1

So, I tried to fly the Strat to TNCM from KCHA, before I had to go to work today, but as usual, I had to quit the flight because something went wrong with COTS.

On the ground while taxiing at a speed of 5 kts (into the wind) the plane was shaking violently, and random gear and flap motor noises were being played all the time. This is not unusual so far. What happened after takeoff is...

I took off with he following power settings:

54" MAP, 247 PSI Torque, 2700 RPM.

As soon as the VSI read positive, I applied the brakes and retracted the gear. Autopilot ON, pitch reference 3.6 degrees nose up, flaps 15 degrees. Immediately, power was reduced to 225 PSI torque, 2550 RPM (METO), flaps were retracted at 158 Knots, VSI reading 200 FPM. Power was then reduced to 194 PSI, 2550 RPM and mixtures were moved to Auto-Rich. Hottest engine was number 3 at 226 degrees Celsius. Perfectly normal.

Climb was at max climb, airspeed 189 knots, climb rate was 300 FPM, gross weight was 122,000 pounds. Around 3 minutes into the climb, the flight engineer warned me of the engines getting warm.
All 4 engines were above 240 celsius despite a forward airspeed of 189 knots, and free air temp of -4 celsius. The temps kept climbing despite a reduction of power to 165 PSI at 2100 RPM. I quit the sim when the number 3 engine caught fire at 278 celsius. The other 3 engines were running in the 250 degree range.

Cowl flaps were set at 3" before takeoff roll, and all 4 engines were below 135 celsius before the takeoff roll. The brakes were released at 28 inches manifold pressure.

At this point, I consider COTS to be a complete waste of time and money. It has not given me even one flight without something like this happening. I have re-installed several times, including a re-install of FSX and Wndows 7. I am about ready to throw in the towel on this one.

Thats a very detailed report and Im sure someone from A2A will chime in but two things that are missing from the report are if you had the ADI on and if the Engineer was controlling the cowl flaps or if you were taking on all the roles...just to help cover some missing parts that might help as to why.

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i7-3820 OC 4.7 |P9X79 LE | 16GB DDR3/2133MHz Corsair Vengeance | EVGA GTX 680 2GB | 480 GB Intel SSD | Window7 64 Pro | Liquid Cooling Kit 360MM w/ Triple Fan powered by Koolance

I was just passing through and caught this.
I'm not the 377 guy around here but let me throw in some comment that hopefully will help.
First off, sorry you're having problems with the bird. Secondly, I know A2A will help you solve them.
I know how frustrating it can be when you're having issues like this but trust me, I think the problem will get solved.
The first thing you need to do is hang in there a bit and give the guys a chance to help you sort things out. Once contact is made with the right people around here, the result is almost always positive.
Let me cheer you up just a bit by telling you that even without knowing the 377 program, it sounds to me like you might have an installation issue that can be solved. It should help to know that many MANY people are running the 377 without the issues you are having so the problem is most likely local.
Hang in a bit as I said. If necessary, send Scott a personal message and let him know about the issue. A2A is a fine group and they will leave no stone unturned in helping you.
Personally, I think what it will amount to is a simple cleanup and reinstall of the 377.
Dudley Henriques

I think this is ADI related. Make sure you have ADI fluid, turn it on, and give control to your engineer and I think you will be ok.

Also, in the future, if you are ever in a situation where temps are exceeding 260 deg, level off, pull power WAY back and get control. Then after things are cooler, resume your climb.

Scott.

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A2A Simulations Inc.

Open the Kneeboard and follow the checklist and notes. They are very good and had me in the air after a couple of mishaps.

You should be climbing at 50"MP and 2550RPM. Speed should be no more than 170kts IAS.

--Dean

He reports using a maximum takeoff manifold pressure of 54". That is well within the parameters of being able to do a 'dry takeoff'. And ADI can definitely be turned off after he reduces to Climb power. In fact, I do dry takeoffs all the time, just to provide some variation. ADI would help in any case, but I'm wondering if there isn't something more going on.

IF he was managing his cowl flaps correctly (or if the VFE was on), I think this might be a Mixture issue. I just did a dry takeoff, no ADI, and the engine temps were just fine. However, I then reproduced this exact profile, only this time, I intentionally made the mistake of having the Mixtures in Auto-Lean. Although I didn't get an engine fire, the temps for all 4 of my engines were above 250. I can also report that, in the past, I have un-intentionally made this mistake, and did accidentally flame one of the engines. My observations were very similar to what the OP reports.

There have been several reports of Control conflicts related to the mixture levers on these forums. It is possible that the graphical position of the levers can appear to be in Auto Rich, when in fact the engines are actually running far leaner due to some configuration issues on the user's machine.

The only reason I throw this out there is because if he simply resorts to cooling the engines via Water Injection, I'm afraid he might be masking something else going on. (His engines should NOT have overheated in the scenario he describes, even without ADI)

Whatever the problem, I hope he gets it working...

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1)i7 980x 4.35 ghz, gtx 470s SLI, Matrox th2go, Creative x-fi
2)i7 2600k, Gigabyte z68x, gtx 285s sli

[quote] "As soon as the VSI read positive, I applied the brakes and retracted the gear. Autopilot ON, pitch reference 3.6 degrees nose up, flaps 15 degrees. Immediately, power was reduced to 225 PSI torque, 2550 RPM (METO), flaps were retracted at 158 Knots, VSI reading 200 FPM. Power was then reduced to 194 PSI, 2550 RPM and mixtures were moved to Auto-Rich. Hottest engine was number 3 at 226 degrees Celsius. Perfectly normal. [quote/]

Scott; Notice in the above where he says the mixture was MOVED to auto rich AFTER takeoff in the climb. If not already in auto-rich, this coupled with his take off MP might be related to his overheat issue.
Dudley

He also only reports getting 300 ft/min. I can easily get 750 ft/min at 160 kts with a full load.

@dieseleldo: I presume "Auto Mixture" is **OFF** under realism settings? It seems your aircraft is under-powered somehow. What were the ambient conditions at time of takeoff and what is the airport elevation?

If the 377 is your first piston-powered aircraft after flying jets it can be quite a handful at first.

Best regards,
Robin.

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A2A/AccuSim. 'nuff said!

ADI was filled before pushback. The ADI low pressure lights are the first things I check, even before checking and setting barometric pressure. The climb was shallow in order to go faster to get more air into the engines. I meant to reply a lot sooner, but work and family stuff got in the way. And, I never let the flight engineer do anything, at all. All he does is FUBAR the turbos and drive the carb air temps through the roof. I do everything except the climb, as the auto pilot takes care of that while the engines and cabin pressurization are tended to. Cowl flaps were set at 3" before the takeoff.

I usually take off with the mixture controls in full rich in order to keep the temps down. Most of the time, this yields higher airspeed and temps below 220 C. I have found that the engines respond well to this below about 2800 ft, and then you should put the levers in Auto-Rich.

Yes, realism settings are as instructed in the aircraft manual. I flew the original 377 since it was first released. It is usually a joy to fly. And personally, after flying this aircraft, the modern jets are just a royal pain to fly.

OK - try this. Switch off the VFE, and triple check in realism settings that auto-mixture is OFF.

Next, set "Clear skies" weather theme.

Set no payload, light fuel.

Go to Heathrow (elevation 80 ft AMSL). Using full rich, start all engines and let them just idle (check 1000 RPM).

After 10 minutes, check all temps.

Ensure cowls are set to 3", set intakes to RAM, auto-rich, and try and takeoff. Without turbo it should be possible to get full takeoff thrust (60" MP). Ensure ADI is on.

Immediately after lift-off, throttle back to the prescribed climb power and switch turbos to climb/cruise. Ensure the lever is at zero.

Level off at 2000 ft. Set for cruise power and configure as necessary for good engine temps with minimum cowl flaps (reduced drag).

Leave for 10 minutes. Does it overheat?

Best regards,
Robin.

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A2A/AccuSim. 'nuff said!

First, if the VFE is screwing up Carb Air Temps and Turbos, then something is wrong with your COTS installation or your FS installation. I've been flying COTS with the VFE handling just about everything and not had any problems ever with either item. He does run the carb temps a bit conservative (i.e. warm), but not dangerously so and it hasn't affected my engine life. Same with the turbos.

However, it is *extremely* important with the B377 to fly the climb profile to the letter. The cooling on the B377 is extremely finicky, just like on the real thing. There were many problems with the R4360 mass cooling, leading to several redesigns of the cowling during the B-50 development because of it. Additionally, of the limited cowl opening and small exit area in the cowl and cowl flaps, accelerating will not necessarily increase mass flow through the engine. In some cases, it can actually decrease the flow due to back pressure as the the air attempts to squeeze through the small opening. This is why it's important to fly the power and speeds prescribed. Try flying the climb profile as marked on the kneepad and see if you still get overheating.

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Dieseleldo

Just double checking here, but in the statement above you mentioned that the ADI was full and that the ADI low pressure lights are off. Before take-off are you physically turning on the ADI with the switch overhead. Even with the ADI full and not seeing any low pressure lights, is not an indication that the ADI is physically switched on.

The second thing that I didn't see mentioned in any of your take off reports is switching the Turbos over to "Climb/Cruise". If your Turbos are still in "Take-Off position and your pushing the climb and by chance your ADI is not actually switched on, I could see smoking the engines pretty quickly.

FAC

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FAC257

I don't quite understand that FAC. I was under the impression that the turbo control override switches simply inhibit the turbochargers in order to avoid an inadvertant boost on the takeoff roll. Accidentally having them in Takeoff position would prevent him from pressurizing the aircraft, but I don't follow how making that mistake would contribute to an overheat.

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1)i7 980x 4.35 ghz, gtx 470s SLI, Matrox th2go, Creative x-fi
2)i7 2600k, Gigabyte z68x, gtx 285s sli

Well, Oskar would be the best source for the technically correct answer, but in my impression, by being able to bring the turbos to bear, enables me to start pulling back on the throttles sooner as the turbos are advanced. The turbo will get warmer but at the same time the engines not having to carry the full work load will stay a little cooler. If the turbos are left in the take-off position while trying to climb, the engines have to do all of the work.


FAC

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FAC257