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Bill, I try to slow down to pattern speed before entering the pattern and then set the prop rpm to 2300 on down wind. With the super charger 2300 rpm is plenty for a go around. Our props will go full fine to the electric stops trying to maintain 2300 rpm when the throttle is partially closed. 2300 rpm gives me a 450 rpm buffer range if I open the throttle too quickly. You may need 2400 rpm. Tracy also recommends not using the gearbox as a break. This procedure minimizes it. Have you adjusted the electric stops to lower the high rpm limit? Tuning suggestions: 1. Get a wideband O2 so you can quickly see and accurately adjust the F/A mixture. In flight use Mode 9 to make corrections in your problem fuel map areas. So you’re not chasing prop/ load changes, set the prop to Manual. I use 2100 rpm for this. 2. Get the EC2 Reader working so you can export your fuel map and graph in excel. 3. Smooth out the fuel map values between known good address points using the exported data and graph. 4. Load the new fuel map in the EC and test fly. Repeat 3-4 times and you should have most of your problem areas corrected. 5. I don’t think it possible to have a perfect fuel map but you can get it close. I replaced my EC2 with an EC3 a few months back. The EC3 has eight fuel map tables for different operating ranges. I still have work to do in two tables. One is the high rpm and low MP area. May be this weekend if the weather is good. Bobby From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Bill Bradburry
Sent: Thursday, November 14, 2013 4:44 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Rotary Digest Activity Rich, I am learning how to land with the prop set for TO power and getting better at it. In fact, I would have to learn all over again to switch so I will probably stay with the former method. The problem is that the prop is such a brake, I have to carry power to touchdown. If I chop power, the plane just stops flying and falls to the runway due to the braking effect of the flat prop. Also since it is electric and somewhat slow to respond, I have to feed power in gradually else it will over speed the engine. I like to keep it below 7100 rpm. B2 I suggest that you reconsider setting the prop as suggested. Perhaps Mark is used to flying fixed props and wants to operate his controllable prop like one of those. this defeats one of the greatest benefits of the C/S prop. When you go to fine pitch, your choice of when, certainly not in your initial decent, (I do it on final,) enrich your mixture to T.O setting and when you flatten the prop to T.O., it acts like a wonderful speed brake, enabling you to do a steeper approach. The other effect is that if and when you have to do a go-around, the prop is already set at T.O pitch, and all you have to worry about is advancing the throttle for max climb. Perhaps I missed the beginning of this string, but it is beyond my comprehension why anybody would spend the extra bucks on a prop that gives you better T.O and climb, while sacrificing possibly some top end speed, and not use it to it's maximum capability, especially in the light of a go-around and landings. Perhaps some dual with an instructor who flies complex aircraft will help. I don't think that you will ever find a pilot of a store bought craft with a c/s prop that would think of landing with any setting other than t.o. fine. Remember GUMPS The M stands for Mixture (rich) the P stands for Prop (T.O. fine pitch). With quadrant throttles, full forward on mixture and prop or mixtures and props. With vernier, mixture in then prop in. If your governor is set correctly and you don't ram the controls in or operate the prop control too quickly, you will find it a great thing to use. If you do not have a C/S governor, as part of your initial setup, you will have created a fine pitch stop and use your pitch switch to get it there and the blade flattening will stop appropriately. Maximize the use of your equipment--- you paid for it. Mark, I tried setting the prop for a more coarse setting prior to landing like you describe. I probably come in too fast, but with the prop set like that, I floated in ground effect almost the length of the runway, then when I added power to go around, I didn’t have much climb power. I tried it a few times and it was similar each time. I could probably learn to land that way, but I gave it up and went back to the brake effect you get with a flat prop when you cut the power. I will try the learning method you describe to see if that fixes the surge problem. You haven’t reported on how your plane is doing with the new panel??? B2
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Mark Steitle
Sent: Thursday, November 14, 2013 2:35 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Rotary Digest Activity I also have an M/T electric prop. I discovered a long time ago that my landings are more predictable if I switch the prop over to manual mode prior to entering the pattern. I typically level off about 3-5 miles out, change the prop rpm to 2100, wait for it to re-adjust itself, then switch to manual mode. This makes the prop behave like a fixed-pitch, and from this point to touchdown I fly it like a fixed-pitch prop. Regarding your surging issue, Tracy suggested to me to simulate a landing, but at a safe altitude. Set up as if you were in the pattern preparing to land, and then put the EM-2 into auto-tune mode. Let the EM-2 tune the settings which are impossible to tune on the ground. Worked for me. Thanks,
Mark On Thu, Nov 14, 2013 at 12:06 PM, Bill Bradburry <bbradburry@bellsouth.net> wrote: Jack, I think everybody is waiting for an opportunity to help someone with a problem. So I am always ready with one that I can use a little assist on. I am having an engine surge and wildly fluctuating mixture when I get into the pattern and reduce the manifold pressure to around 15 inches and below. I have an MT electric constant speed prop, so my engine rpm at this time is pretty high, usually around 6K. This is an area that can not be tuned on the ground and I suspect that is the problem, however, the MAP table is at the factory setting of zero in areas that I have not tuned. It can get pretty exciting when it starts so I would like to get it ironed out. Others having similar problems or how to go about the fix? Bill B
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of marv@lancair.net
Sent: Thursday, November 14, 2013 12:08 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Rotary Digest Activity HI Jack, I checked and found your subscription to be intact. It appears that there has been no Flyrotary traffic since 11/3. Very strange, indeed... but it happens I guess. Could be everybody's buttoning down for the winter... we'll see. <marv>
"Jack Hilditch" <wmjack@t3cs.net>:
> Good morning,
>
>
>
> I watch for the digest every morning but the last one that arrived is
>flyrotary
> Digest #3834 dated 11/04/2013. Have I been unsubscribed for some unknown
>reason
> or has the list simply gone quiet?
>
>
>
> Thanks very much,
>
>
>
> Jack
>
>
>
> Jack Hilditch, MCP
>
> T3CS Systems Support
>
> 205 Storrs Road
>
> Mansfield Center, CT 06250
>
> Cell 860-729-6948
>
> <mailto:wmjack@t3cs.net> wmjack@t3cs.net
>
>
>
>
>
>
>
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