OpenTX / Taranis / Full House Sailplanes

[makattack]

Ok, I was chatting with Andre last week, and we were talking about new planes to put under the Christmas tree, erhm... for ourselves

Anyhow, I mentioned I was torn between a HH Radian and a FZ Calypso. They're in the same price range, and I have the micro/UMX Radian, which I do love. A bunch of folks at my RC club also fly the full size Radian (and the micro one) at the flying field. There are also a bunch of advanced soarers who have the fullhouse, built up, sailplanes who winch launch, etc.

My curiosity with learning to fly an electric launched foamie glider resulted in a failed self-control attempt at not ordering the Calypso. It was made worse by TowerHobbies having a scratch-and-dent TX-Ready version with only minor box damage for sale. I pulled the trigger, and $170 later, I'm an owner of a Calypso with some spare props and an Anylink2 in case I want to use the RX that comes with it.

Turned out the RX was one of their stubby little antenna ones, and in a soarer with the potential for getting into big thermals, I worried about the range and lack of diversity. So, that RX and the Anylink2 is going in storage.

This means, I will be re-purposing a FrSky L9R RX (the long range RX) and splitting the ailerons to separate channels.

I've already cut out the flaps on the wings, and installed flap servos using 9g servos I already had. In experimenting with them using a servo tester, I found they had plenty of down flap range when setup with max mechanical throws to allow for me to program them as flaps or spoilers. First question, for anyone with experience with this stuff: Does it make sense to have the flaps configured as spoilers as well? I know I can simply program crow / spoilers with the ailerons for landing, but do you think it might be useful to have flaps that can also act as spoilers / add reflex near the root of the wing?

My next step is programming a model in OpenTX for this plane, and I already suspect I'll start off with the throttle on the normal throttle channel / left stick (I fly mode 2), and the flaps assigned to a side-pot on my Taranis. I may flip that around later once I get more experience. For the first few flights, I probably won't even touch the flaps and will only gradually add them at altitude to see what happens.

On that note, any Taranis soaring pilots have any experience/insight into all the exotic soaring mixing possible? Again, I see the configuration changing as follows:

Beginner stages: Throttle on left throttle stick. Flaps on pot.
Intermediate stages: Setup launch mode where throttle is on left stick, when soaring mode, where left stick = flap (full down throttle = 0 flap, full up throttle = full flaps)
Advanced stages: Set up soaring modes: thermal with a little camber dialed in to both flaps and ailerons, crow/landing mode: with aileron reflex mixed in with the flaps, here's where I might be experimenting a bit -- I'd like an additional brake mode where I keep the ailerons in their default configuration, but have the flaps work as spoilers instead of flaps, adding reflex to the root of the wings. As I see it (from a non-aeronautics engineering/laymans perspective) this might be safer than flaps down in terms of preventing tip stalls.

Anyway, I guess it won't hurt to experiment.

 

[mjcp]

Welcome to real flying... i.e. Gliding!

Here's a link to RC groups and a post with a Taranis setup I did for a guy with a Radian...

RC groups


There are 4 flight modes:

Launch (Sw_A Down),
Cruise, Thermal, Speed (On Sw_B when Sw_A Not down)

Sw_A down overrides the other modes.

All the Flight modes are flat in this file, CROW is active in all 4 modes. Its is straight forward to add flap and reflex settings for various modes (Launch, thermal, speed etc by adding a flight mode specific mix to the relevant Ch)

This was for flaps on a "Y" connector, but your 90% of the way there... just pick another Ch for the second flap and duplicate/adjust the mix items to it...

let me know if you need a hand...

mjcp

 

[mjcp]

About the flaps as spoilers...All the crow brake setups I have seen have the flaps down, Ail up to avoid the tip stall situation... if your wing stalls in the section with flaps, its not really a tip stall... just a full stall!

On landing... you tend to want a slower approach and to bleed speed as you descend. On a "true" glider, you will build up speed quickly as you descend (trading height for speed) so you want to shed the speed (either by climbing - not great on landing) or through drag. This is where brakes, spoilers etc come in... In various ways, they reduce the wings efficiency, add drag or reduce lift. Crow braking gives flaps (good for drag and improved lift at higher angles of attack) but also reduces lift at the tip by popping up the ailerons. The benefit there is the reduction in likelihood of a stall starting at the wing tip with added drag from the raised surface.

It might be helpful to also think about how a real glider lands:

The pilot selects a landing configuration: flaps and often pops the spoilers a little (not all gliders have flaps) and an aiming point. The spoilers are then used to control rate of decent, elevator inputs are used to maintain correct air speed. A lot of RC pilots get this back to front...

So, I'd say: Flaps good, Crow good, flaps as spoilers.. not seeing the benefit.

mjcp

 

[makattack]

Thanks for the recommendations and your example .eepe file mjcp! I really appreciate it. I've downloaded a bunch to see how others do it, but I definitely want to see how different folks approach it. I'm tempted to just put a Y on the flaps, but I do have enough channels on my 9ch RX, so might as well use them, right?

I've pretty much decided the flaps as spoilers won't give me anything other than a more complicated setup, so I'm going to change the flap to mechanically limit their throws to 0 and full / close to 90 so that the servos won't be as stressed.

 

[HawkMan]

I'll just say othat I recommend using an X8R instead of the L9R receiver.

The X8R has more than enough range to fly it till you can't see it anymore, but more importantly it has telemetry so IF you lose the plane, you can find it again. If it gets away from you the range of the Tx isn't an issue with this size, the range of your vision is.

it also means you can tack on useful stuff like vario and pitot.

 

[Craftydan]

Mac,

Can't speak to the Taranis (Don't have one) but as for the 4 servo wing in the Calypso . . .

Match the throw on the ailerons.

Full down aileron angle is a VERY aggressive flap setting, so that's plenty enough down. Setting it so that it can have the same throw as the ailerons means you can have it's normal cruise mode use full length ailerons by mirroring the aileron throw on the flaps. Do setup the flaps on a 3-position switch -- If I catch a thermal, a step or two of flaps helps you make the best of it.

It also means you can have a balanced crow with good "drop gracefully out of the sky" performance -- flaps go full down, ailerons go full up. I have it on mine, and I can set her at my feet on a whim, where clean or pure flaps, I'll usually have to take a walk -- she floats forever when clean. That means 4 independent channels just for the wing, but on an 8 channel RX, that's NBD.

She will loose aileron authority when crow is fully deployed, but there's so much drag on the wing when that happens, it's usually not a problem -- that and she still has a rudder I've got my crow set to linearly deploy on my throttle stick, with the "mix" switch being the same for the throttle cut -- when the motor stick is armed, the crow is off, when the motor is disarmed the crow is on. The logic behind this is you don't need to press the gas and the break at the same time.

Keep in mind, you'll need to mix elevator with flaps and crow . . . but that should be done to trim.

Typical flight profile is throttle up and launch clean (FYI, if you're using the stock prop, the stock motor/ESC can still handle a carbon 10x6 and will launch like a rocket) rotate at the top and throttle stick down(in that order -- you don't want to stall out in your climb) then drop a single step of flaps to settle in. Bring the flaps up, and hunt for lift. see a wobble, turn into it, and drop a step or two of flaps. fall out or abandon it, then back to clean and back to searching, or launch again. When it's time to land, with throttle stick min, flip the throttle cut, lineup, and as she approaches open the crow smoothly to break to a stop at my feet. doesn't take much time to get used to it, when you've got good control

 

[makattack]

Thanks for all the great advice Dan and HawkMan! Yeah, I pulled the L9R from an old FT Electrohub tricopter build, because the way I fly that, I don't need a long range RX... but what Hawkman said is correct. I would rather have the flexibility of getting telemetry from the X8R. I do have an X8R in another model that I can pull out and swap the L9R into. Makes more sense as that other model doesn't have much space in the fuselage for additional sensors/etc.

That said, I think it'll be quite some time before I think of adding vario or airspeed sensors to this plane. I hardly can see myself looking down at my TX while flying. I'd be too afraid of losing sight of the plane. An audible or vibrating alert just seems a bit too intrusive... My club runs ALES (Alt. Limited Electric Soar) and RES (Rudder Elevator Spoiler -- I wonder if I could enter those if I have a spoiler only mode? I'd have a big disadvantage with a heavy motor/prop hanging off the front as balast only, but I had heard someone modified their Radian with a winch hook and strengthened wings and was able to enter the contest) events in the Summer, so if I wanted to humiliate myself, I could put an entry in at least the ALES event. On a side-note, I did participate this year, in the ALES, but as the volunteer who was responsible for lunch...

So, one more question: I like the idea of using the equivalent of a throttle kill switch to select crow/brake mode. Makes sense. Now, for the linear deployment by using the throttle stick/channel, do you have it so that the full throttle/stick away from you is "zero brake"/fastest/cleanest wing, and "zero throttle"/stick max down towards pilot is "full brake"/slowest? I can see myself adjusting to either setup, but I thought I'd check to see if there's a convention to this.

 

[Craftydan]

I've seen it done both ways . . . and done it both ways

On my Calypso, since I'm generally starting a launch or landing from 0-throttle, clean is at the bottom, and all cruise and thermal modes are with throttle stick down. Not really been an issue, since I rarely switch rapidly between throttle and crow, and the only case I'd want to do this is an aborted landing, at which I'd want to go from full crow to full throttle at a flip of a switch.

On my DLG, I go the other direction. I've gotten used to my hotliner's flap switch being spoiler-neutral-flaps, and I've setup the throttle on the DLG to do the same -- midstick is clean (with a beep) down is down, up is up. Yes it messes with my head sometimes . . . but I haven't really used it that much. Mostly I flip between the clean and slow-cruise fixed positions, and that's generally enough to land it in my hand a sufficient percentage of times that the linear flaps are infrequently used.

Your call, but for the Calypso, crow strength follows throttle strength makes sense to me . . . at least a little

 

[mjcp]

I fly my 4m DG on an X8R with Vario and GPS. With the "Amber" voice pack, you can have it call out Altitude form the Vario (mines every 10 seconds) and get Vario tones so no need to look at the display !

Cant see if the L9R has sBus interfaces... so might not be able to link to the modern Varios/GPSs

mjcp

 

[makattack]

The L9R does have SBUS but is missing the Smartport, which I believe is what those telemetry devices connect to, so it can't send telemetry data back to the TX other than RSSI. They use that extra port for an extra channel, and with the reduced telemetry, they have more bandwidth for longer range (in theory).

So, I've made my initial programming configuration. I've got launch, cruise, and crow/brake, and full aileron modes. I still have to program in a thermal/camber modes, but then when I started wondering how I might figure out mixing elevator with the different modes, for trimming, I started searching for trim calibration suggestions with soaring/gliders and opentx, and pretty much found what looks like a great setup:

http://www.rc-soar.com/opentx/setups/esoar/index.htm

Sheesh... that was about 2 hours I could have saved last night, but alas, it was educational. I haven't ditched my setup yet, but will be comparing it with the above, which has the trim calibration features I was wondering about.

 

[willsonman]

I'm getting into the Taranis now and am looking to setup my DLG. 4channel spoilerons (flaperons) with elevator and rudder. I'm a bit at a loss as to where to start for this as there are several flight modes needed for a DLG.

 

[makattack]

I'm getting into the Taranis now and am looking to setup my DLG. 4channel spoilerons (flaperons) with elevator and rudder. I'm a bit at a loss as to where to start for this as there are several flight modes needed for a DLG.

I basically ended up duplicating the effort of a lot of other folks, partially so I can use it as a learning experience, but also because with other example configurations, one needs to also spend time examining, customizing, testing it and may take as much effort as starting from scratch.

That said, I like being able to see how others do things so I can pick and choose those elements appropriate for me.

All the examples detailed in this thread, coupled with this overview of mixing on the OpenTX software really helped me:
http://open-txu.org/home/undergraduate-courses/basic-airplane-set-up-with-taranis-2/mixer-613/

I've added my version of a full house Calypso setup:
View attachment calypso.zip

The one odd thing in my setup, is that I've enabled aileron control in brake mode. I'm not sure how useful that'll be, or if it's a dangerous thing to do, but it's easy enough to disable by deselecting the flight modes from the mixes for the flap/aileron servos.

The configuration assumes the following RX servo/esc connections:
1: Motor
2: Elevator
3: Rudder
4: Aileron Left
5: Aileron Right
6: Flap Left
7: Flap Right

Oh, another odd thing... I have a camber setup using the right slider / pot, but I didn't bother limiting it to just undercamber... so, if one wanted to, one could push for fully reflexed trailing edge of the wing... I probably won't experiment with that unless I have a bunch of altitude.

 

[HawkMan]

Actually, I don't think the L9R even send RSSI, as it doesn't have the transmitter part at all.

 

[Craftydan]

Oh, another odd thing... I have a camber setup using the right slider / pot, but I didn't bother limiting it to just undercamber... so, if one wanted to, one could push for fully reflexed trailing edge of the wing... I probably won't experiment with that unless I have a bunch of altitude.

Which is the whole point of spoilers and crow -- safely bleed energy off rapidly.

Spoilers do it while still giving better wind penetration (in case you're also fighting to get upwind as you plummet out of a strong updraft), where Crow evenly increases your drag (even lower/faster speed-for-altitude exchange, but more susceptible to wind).

Neither make the airfame more efficient -- quite the opposite -- but the make the airframe better suited to the air when you want to come down NOW and/or move quickly against the wind. More often than not, they're about burning altitude to land or race to the "next" thermal, not about soaring . . . for sure, play with it, but use it wisely and it's a good tool to get her back to your feet.

 

[makattack]

I maidened my Calypso setup with the 4 servo wing, and was pretty pleased with it despite the less than ideal, gusty, windy conditions. Those conditions made the landing approach a little dicey and took a couple approaches where I had to land in launch mode so I could power away for a go-around. This glider sure does get tossed around in the wind especially near the ground. Despite that, the stock motor and props seemed to handle those conditions well enough to get me out of trouble. I was able to finally land it with a nice VTOL style zero ground speed landing when the wind was finally steady vs. all over the place.

When I had it at altitude, it was essentially slope soaring and had it up there about ten minutes or so before I ended up in some awful sink or downdraft that had me switch back to launch mode again.

I ultimately setup my Calypso with the following:

FrSky X8R receiver with a SP40A 40A Voltage/Current sensor (just for conditions like today when I might have to use the motor more than expected)
Flap servos setup for full mechanical throws (reflex and camber) on two independent channels.
Ailerons on independent channels.

I've got it setup for the following flight modes, but only ended up using the Launch and Cruise modes only.

Launch: Motor on throttle stick, flaps on left slider as determined by SF switch which is also throttle kill (pull towards pilot to kill motor)
Cruise: Motor disabled, throttle controls flaps
Thermal: SG adds camber to ailerons and flaps. 3 positions as determined by the SG switch.
Brake: Butterfly/Crow with roll control
Full aileron mode: Flaps and ailerons act as one

In all modes except thermal mode, the right slider adds camber or reflex to the trailing edge using all four servos. Push away from neutral = reflex, pull towards pilot = camber

SA and SB switches select the flight modes, but not all permutations covered, so anything not covered = launch mode (default) with no motor.

Channel mappings:
Ch1: ESC/Motor
Ch2: Elevator
Ch3: Rudder
Ch4: Left Aileron
Ch5: Right Aileron
Ch6: Left Flap
Ch7: Right Flap

Unfortunately, winds tomorrow are projected to be about the same 10-20mph range despite the warm 60F temps. Ah well, I won't bother flying in that as the landings are a bit stressful when the plane randomly changes course with the wind as it nears the ground.

 

[makattack]

Wowzers! Ok, I had a great holiday weekend of Calypso flying. Wow! It started off with me mostly flying by myself on the 24th in the AM. I arrived as a few folks were wrapping up and leaving. The flights were good, but I was still just trying to get used to flying and in particular, landing. I was still too chicken to deploy the crow, as when I experiment with them at altitude, it tends to balloon a little more than I would have expected. Maybe I need to limit the amount of down flaps or mix in some down elevator. I'm also getting used to having flaps and flying with them. Unfortunately one incident this past weekend didn't help settle my nervousness with them.

I had to do the glider "walk of shame" where I had to walk clear to the other side of the field to retrieve the plane since it landed (ever so gently) about as far away from my foot as you could possibly get. Yeah, I won't be entering any contests anytime soon!

The next day, Christmas Day, I again show up to the field in the AM, and this time a few of the expert glider pilots were there with their impressively large 6M motored sailplanes. They were surprisingly curious about my little 2M Calypso and asked about it. Being more of a tech geek, I was happy to show off all the heavy training aids I have since thrown in the fuselage (current/voltage sensor, variometer) which feeds back the values to my Taranis. I setup the vario to report altitude verbally using the momentary switch only for now. One of the pilots was offering suggestions which I think I'll implement, as it all makes sense to me, so I'll post a new .eepe later when I get a chance.

His recommendations:

1) Set throttle to a switch, and use one of the sliders (most likely left) for throttle value
2) Mix in a zero flap override for the throttle/launch mode (more on this later)
3) Right now, my throttle stick gives more flap and more butterfly, the higher the stick goes. Reverse this. Make it so clean = highest stick position.
4) Because I have such small flaps on the Calypso, consider mixing the ailerons to work with the flaps as flaperons. I have a camber setting that is basically a "lite" version of this, but his suggestion does make sense. Doesn't hurt to experiment with it.

Anyway, with the flexibility of OpenTX, this isn't too hard to do, and I like the general idea.

Ok, back to why flying this plane has been so great this past weekend despite a few mishaps.

Christmas day was mostly me flying around the same way, getting more comfortable with using the flaps, and crow/brake at lower and lower altitudes. There was hardly any winds, so it was a good day to experiment. As I was about through with my day, these two guys pull up next to me with these big swamp boat looking fan contraptions on the back of their cars. I say hello, and before I realized what they were doing, they introduced themselves as PPG pilots and asked if I thought it would be ok to fly from our field. My response was basically "I have no idea, but I don't see why not? Just realize you are close to being five miles from Hanscom Field / Hanscom AFB"
and pointed in that direction. One of them responded "oh, yeah, I used to live on the base, and still work there." Turns out he's active duty AF. Haha. I withheld my snarky comeback with "why don't you just fly from there?" but his friend asked for me, and his response was that he did get permission once but that it was too much of a pain. He did add that their radar didn't pick him up due to his slow speed and their default setting for filter out anything slower than a minimum speed.

Well, at this point, there was no leaving for me. I had to watch these guys setup and fly. Heck, I even helped carry their wings and wind sock out. Anyway, it was great seeing this at my flying field : https://goo.gl/photos/h15AEfetddAaV1wH6

I return the following day (26 Dec) and was surprised at how busy the field was. The guys with the 6M sailplanes were back, with a bunch of other folks mixed in, including folks who looked like they were flying for the first time. I saw a few buddy box setups and a whole lot of Horizon Hobby UMX cubs with safe, and a few Sport Cubs, 3Ch trainers, etc. There were also numerous families and dog walkers running around the field. I mentally noted that this was going to make my landings a little interesting.

I watch the 6M guys launch, then got the nerve to toss my foam glider up. I decide to fly out over one line of trees that marks one of the fields boundaries with some farmland. As soon as I got over there, I noticed my plane was just going up on it's own. I had long ago turned off the motor, and thought to myself "Oh my, my first thermal!"

One of the 6M guys noticed my plane was going up and asked if I was motoring up. I said, "nope, I seem to have found lift" and he immediately flew towards that area. He was higher up than I was, so I initially wasn't too worried. That is, until it looked to me like both planes were about the same size. At this point, both planes looked to be about the size of a UMX radian, but I wasn't getting RSSI warnings yet. Nevertheless, they were the same size against the sky and I was now worried about my inexperience being a problem and potentially crashing into him. At this point, I announced I was getting nervous about hitting him and I'm bailing out.

This was received with simultaneous laughter from the other glider pilots who said "uhm, his plane is three times your planes size, and since they look about the same size, that means his is probably about three times your altitude!"

Ok, I just had my first lesson in judging separation and altitude from the ground!

Nevertheless, I was getting nervous with my plane looking so small. It was also coinciding with the field getting more crowded, which would have made landing a bit tricky, so I stayed in the lift for a little longer, but a short time later, decided it was enough excitement for me considering this was the first really big lift I've ever experienced.

I decided to fall out of it, and if only just get low and motor around a little so I could burn off the 3S pack which at this point was still reading over 12.2V. I get it down to about 100' AGL and fly over the field a few times while looking for a good landing approach and clearing. An area near where we were standing cleared, but the only way to land without flying over the parking lot (frowned upon) was to land with the wind. Not ideal for a novice like me. I'm too unfamiliar with what a brake/crow setup would do in a downwind run, so I decide I have to land it with flaps only. Except, I'm not slowing down enough and I'm way too high, so I overshoot my landing, and it starts to go past me. As it does that, I see two guys who were buddy boxing, walking out to the field, and I shout "heads up!" as they were kind of in my super long glide path. One of them had to duck down, but the plane would have been over his head anyway, and I have to apologize profusely for that scare. It landed ok, but thank goodness it was in a patch of rougher grass that slowed it down well. It definitely came in hot and was rolling on the ground for a long run -- darn that great landing gear. I also happened to just miss rolling through a big pile of dog poo.

Well, that was scare/mistake #1. Trying to do something I wasn't familiar with and making wild guesses: landing downwind, trying to use flaps only.

I hang around, watch others fly, while getting the nerve up to throw my last battery in, and launch. At this point, I probably should have packed it in and called it a great day. BUT NO.... I still had one fully charged pack, so just one more flight!

I throw in the battery, throttle up, toss, and as I return my left hand to the TX, I brush against the switch I had setup for flaps. About that same time, everyone started shouting as my plane was doing this weird kind of hover and eventually performed a stall turn. I had even noticed that the flaps were fully deployed as I stared at the plane, but quickly reset the switch and cleaned up the wing. I don't know how I recovered from a stall turn, but yes... the Calypso can indeed perform a hammerhead maneuver at relative low altitude (about tree top level.) People started to congratulate me on the recovery and one of the guys at that point suggested I mix in something to disable the flaps in launch mode. That'll be the first thing I'll do, before my next flight.

This just threw me so much that I kept the flight short, and made a poor landing that again, took the whole length of the field and had a long walk of shame to recover the glider. Heh, the people who were walking their dogs remarked that it looked like such a great landing, it was so graceful and smooth... I didn't have the heart to tell them that it was actually terrible because it was so imprecise and far from where I launched!

Well, despite all the mishaps, it was a great flying experience with this Calypso, which has become my favorite plane to fly. Now, to learn how to land...

Oh, BTW, I was a little glad to see I wasn't the only one making big mistakes. Other than the folks who just got their SAFE planes and started flying for the first time (sadly, one had a fly-away and had to go look for it, but it didn't look damaged at all despite landing in a marshy area), the 6M glider pilots had some mishaps too: One bumped his head on launch -- loudly... I heard the bang. Another miswired one of his ailerons so that he only had flaps and one aileron. That didn't stop him from having a great flight -- in fact, that was the same flight where his plane was about 3 times above mine in that same big thermal.

Well, just posting this in case it might help anyone else starting out with gliders...

BTW, if it seems like the flying field I use is a little chaotic, yeah, it can be. It's a AMA listed field, but it's shared use. On any day, there can be model rockets, foamies, 3D planes, helis, and now manned PPG pilots all vying for the same space! That's not including all the walkers/hikers, dogs, frisbee games, etc.

I love it. Wouldn't have it any other way. It's one of the reasons why I joined. If anyone wonders about how welcoming we would be to the PPG folks, well, one of the guys mentioned running into our club president while he was scouting out the field as a potential launch/landing site, and he said the response was great and welcoming. I'm not surprised. It's my main reason for joining.

 

[makattack]

I've updated my model configuration as detailed above. We'll see how much I prefer this.

* Flaps disabled in launch mode
* Variable throttle via left slider
* SF- = no motor flight modes / throttle hold, SF+ = launch mode
* Throttle high = clean, throttle low = dirty: full flaps or brakes depending on mode
* Added SC = Vario mode (beeps), SC- = read altitude every 10s

New OpenTX .eepe file: View attachment calypso.zip

 

[Craftydan]

Mak, Sounds like a great weekend out at the field

I can see a full wing camber being a good thing, but I'm usually happy with the extra lift from a mild drop on the inner flaps. YMMV.

Either way, congrats on catching a thermal (and don't you think those sailplane experts won't keep watching you to steal your lift ). BTW, that's almost the situation you'd want/need a spoiler mode for -- intentionally falling out of a strong thermal. It's the cleanest way to trade lift for wind penetration without picking up too much energy in the process.

For landings, if you get an uncrowded day (when the cold finally kicks in, you'll get more of), practice, practice, practice landings. That's the only way to get consistent "at your feet" performance, particularly with a floater like the Calypso.

Also, while you can't do good touch-n-go's on a Calypso, you can do repeated approaches, but you will have to get used to the launch. Biggest thing you'll need to know for a repeated approach is where the "last chance" is for re-launch -- too low/slow and deploying your prop on launch will stall and crash your airframe instead of launching it (positive side, the impact will be more embarrassing than anything else). Once you know this, you can start to build a good guess for "so far that direction" equals "at your feet" . . . and you can start practicing/scoring approaches without actually landing.

After that, the most effective advice I've had for gaging the approach is to have a consistent landing pattern (distance wise) and gage the altitude when the airframe crosses opposite you on the "downwind" leg (by traditional pattern names). Eventually for each airframe you'll be able to gage "to high/too low/just right" altitude for the pattern from that point. First goal in the repeated approaches is to find that sweet-spot altitude where all you need to do is fly the pattern and it lands within a short walk. Once you have that, You can break the consistency a bit to make up for missing that altitude window -- Stretch or shorten the pattern by adjusting when you turn "base" or bleed energy by feathering the crow through "base" and "final". Get that sweet-spot in your head, and stretching/shrinking the pattern and bleeding energy should be quick practice to the perfect spot landing.

BTW, always keep in mind, you've got a motor and you can go around. Unless you've been abusing your battery and you see lights flickering, when you see someone in the approach, abort. Fire up the motor and get away! One more reason to get the bigger prop, so she has some WOT vertical performance in a pinch (and it's neat to stand her on her tail the whole launch, but that's another matter entirely ).

 

[makattack]

Thanks Dan! That's certainly great advice. Yeah, I have to remember / practice with flipping the switch to power up the motor again. I think on landing, I have to remember to keep my finger on the two position switch that would power up the motor in case I need a go-around. Yep, more practice at the field when it's less crowded!

Great advice too, about the pattern practice. I've noticed I've been getting too brave about making too tight a turn at too low an altitude after my downwind leg, so much so that it makes me nervous. All simply because I feel like I need to get as low as possible on the approach so as not to overshoot the landing. Ultimately, I think I'm compensating in the wrong area for my lack of comfort with the brake/crow setup.

We have a "frozen finger fly in" on the 1st day of the new year, and I'm planning on going. Hopefully I'll be able to practice a little before then.

 

[mrwzrd59]

Gee whiz! I like to fly my Calypso because it's so un-complicated! I cant fathom adding a bunch of functions to mine! It flies perfectly right from the box with the exception of changing out the ESC for a Castel 25 with a programmable brake. The stocker would not truly stop the prop so it allowed too much drag in glide. Other than that, I just countered the tendency to pitch up with the flaps half way down. I ended up with 30% down elevator mixed with half flaps and fully raise them before touchdown at my feet. Yea, it'll float on by if you're not concentrating and allow it to do so but "crow"? Na, pretty dumb and totally un-necessary in my humble opinion.
On a hot summer day with winds less than 6 mph, I can get flights to last as long as I have patience for! So far I've knocked off after 40 minutes aloft, simply because my neck was getting sore! If I would care to set in a recliner, I could keep her on the edge of my sight for hours, that I'm sure of! Save the wacky set-ups for a bigger sailplane and install spoilers for your "spot landings". BTW my Hangar 9 ASW 20 4.7M motor-glider is on the bench as I write this so I will be going "full-house" soon enough, thank you. My only other "upgrade" was to change out the plastic spinner and props with aluminum and carbon fiber...The stockers were junk. Enjoy!