sbeecham

Could some one tell me how to program a mix that will retract flaps when you move the throttle past a certain point. ie when you need to do a go around.
My old JR 9 and 11 channel 2.4ghz radios have this feature built into them.
I now have a Spektrum DX20 but I'm afraid the programing is a bit beyond me.
Any help would be greatly appreciated.

Thanks

rgburrill

Let's see. I'm on final and just about ready to touch down when a rabbit runs onto the runway. I hit the gas to go around and my flaps go up. I stall because I'm too slow and destroy my plane.

BarracudaHockey

My Feedback: (11)

Thats my thoughts too

sbeecham

Thanks for your input. I have been using the auto land system for about 10 years without a problem ( touch wood)
I also have the flaps on slow activation which gives the engine time to power up before the flaps fully retract.
I don't use this system on my turbine models for that reason you mentioned

Thanks again

BarracudaHockey

My Feedback: (11)

I'd have to play with it to see but my first thought is the digital switch setup where you can set points on the throttle stick to act as trigger points for things such as a mix. You might want to start there.

r ward

I would call the radio's customer service dept, or look for a "programing assistance" phone number in the owners' manual.

AndyKunz

Or better yet, just ask Andy.

Like RG says, this is a great way to crash. That's why we didn't duplicate the feature when we made the Spektrum radios.

You CAN program it manually, though. Having a DX20 helps because it gives you all the tools to solve it several ways.

My recommended method would be to use the Flight Mode function to control the flaps. There are a couple reasons I recommend that anyway, but right here the easy answer is because it allows you to define multiple input devices to define the proper mode. I would define the Flight Mode system with a 3-position switch as the primary input (B or D). Let's just say you are using D for this example. We'll do this in a few stages so it makes more sense.

So you set up D so that with the switch in position 0 you are in normal flying mode. Let's call it "Cruise" (which is also available in speech). Gear is up, flaps are up, throttle can be anywhere you want.

Let's set position 1 to "Takeoff" or "Launch" mode. Flaps are partially down, gear is down, and throttle can be anywhere you want.

That leaves position 2 for "Landing" mode. Flaps are down at least to the Takeoff position, gear is down, and throttle is down (anywhere less than say 75%).

Be sure to set the timing so that there are several seconds from landing position to takeoff position. You'll see why later.

You configure these names in the Spoken Flight Modes screen. Don't skip this step - it's virtually impossible to finish the process if you don't change the names!

Put that configuration into your Flap System, using Flight Mode as the switch, so the flaps go to appropriate positions based on switch D (which is being called by the Flight Mode function).

If you have retracts, you can optionally either put them on their own switch (typically A or H), OR you could use Digital Switch Setup to change the Flight Mode switch so that the position is 100% when the gear is supposed to be up, and -100% when it's supposed to be down (two positions). Your choice. Do it on Flight Mode and you really don't have to worry much about landing gear-up.

Once you're happy with how that works, it becomes time to add Throttle into the equation.

Go to the Flight Mode setup screen and now change the second switch from Inh to Throttle Stick. You can do that by opening the field by clicking the roller and then wiggling the throttle stick. Click again to save.

You will notice that the bottom of the screen changes from 3 to 5 flight modes. Click on NEXT so we can edit the FM table.

Now you can see why I told you to change the names. The display only has room for 4 characters per mode (I used FLY, TAKEOFF, and LAND). If you hadn't edited them, you would see the word "FLIG" in all 12 positions! That's because the default names are Flight Mode 1 to 5. You can't edit that and know what you're doing.

The D switch controls which row you are on, and the throttle stick controls which column.

The top row corresponds to when the D switch is in the 0 position, for normal flying. It doesn't matter where the throttle is, so it says "FLY FLY FLY"

The middle row says "TAKE FLIG FLIG" (which is short for Takeoff, Flight Mode 4, Flight Mode 5). You want to change this to TAKE TAKE TAKE because you want to be able to have the throttle ignored for flaps in this position.

The bottom row says "LAND LAND LAND" - but that's not what you want for an Auto Land system. Change it to LAND LAND TAKE.

NOTE: You position the cursor for editing a position by moving the switches (D and the throttle stick) to each selection and clicking the roller. When you're done editing all the positions, click the roller again to save the settings.

What this configuration does for you is when the flaps are down and the throttle is below about 75%, the flaps are in the full-down landing position. If you should abort, the flaps will only go up to the Takeoff position (not fully up, like JR does) so the throttle should be coming on before the flaps rising cause too much loss of lift.

Be sure in your Flap Setup screen that you have the timing set for several seconds between transitions. You need that for this to work nicely.

If you want to change the throttle position where the flaps go up, you do that in Analog Switch Setup. It should be pretty intuitive how to use that screen.

Andy