Official Freewing Twin 70mm AL37 Airliner Thread

[406PIlot]

Well my graphics from Callie came in. I started cutting things out and lining them up and found an issue. For the first time that I've gotten graphics from Callie they had a problem. The door that is supposed to over the wing on each side is in front of the wing / about 7 windows to far forward. Any passengers that go out that door will most certainly fall to their death HAHAHA.







Everything else about the graphics seems to be correct. The length and the way they line up is all good. It's just that over the wing door that isn't over the wing. It's the same for both the left and right side graphic.

I've contacted Callie an am waiting for a response.

[GliderGuy]

Really gave the new gal (and me) a workout today. Tons of flights in over 7 hours of flying. She’s solid as a rock...did some “way over there” flying, so the range is definitely good. Systems never gave a hint of any issue...as it should be.

I hit some STRONG thermal gusts causing go arounds. On a couple of take-offs, it took full control throws and lots of power to keep wheel side down when the thermal gusts were encountered after lift-off. Exciting! Good soaring weather is almost here!


-GG

[406PIlot]

406Pilot I may come up this Spring there are a few good friends of mine I haven't seen or flown with for a year or so. Chris, Earl, and Clay to mention a few. I will bring my AL37 with. they are an awesome flying Bird. You will love the graphics from Callie I have ordered many from them. I am going to Sun City and Phoenix for two weeks this month to see my Sister and my younger daughter, I do plan on going to the june flyin too.

Great group of guys at our club! I can't wait for our fly-in.

[GliderGuy]

Update....Perfect weather today. Maiden went well. I will attempt to wear it out today!

Flies great. Flies inverted better than the prior birds.

-GG

[Ian H]

Someone at the field got this cool picture while doing a slow fly by.

[Scale Freak]

GliderGuy, Hope it goes well! I'm just waiting for the snow to go and then the field to dry out, if its not a stupid wet year again like last spring, I should be out in about a month or two. I envy those who can fly pretty much year around. lol

[GliderGuy]

As for stall speed, the decrease is more than a little when you compare no flap stall to full flap stall speeds, ever seen a Dash7, or a Buffalo do an approach with 40 deg flap, at speeds matching a C172 on final, its awesome!

I agree, but what I stated was that stall speed doesn’t decrease a lot from 10-15 degrees and full flaps. Not as much as one would expect. It’s a non-linear relationship.....flap angle vs stall speed.

Said another way....flaps mainly increase the amount of drag when extended beyond 10-15 degrees. It will be a good experiment to try regardless.

On topic of the AL37....I got finished and plan to maiden tomorrow. Light winds are forecast all day.

-GG

[Scale Freak]

Glider Guy, yes as a full size licensed pilot I am aware of the flap angles and lift/ drag relations. That being said, our models have disproportionate amount of thrust to weight that overcomes a lot of the drag at mid flap settings. Its an experiment for sure, and only true real world testing will prove this theory right or not. As for stall speed, the decrease is more than a little when you compare no flap stall to full flap stall speeds, ever seen a Dash7, or a Buffalo do an approach with 40 deg flap, at speeds matching a C172 on final, its awesome!

[Wild Man]

Callie shipped out my graphics today! It's a bit windy today, but I'm itching to get this thing back in the air. I just can't believe how much I like the AL37. I am extremely surprised. Such a great flyer.

I can't say enough good things about this plane.

406Pilot I may come up this Spring there are a few good friends of mine I haven't seen or flown with for a year or so. Chris, Earl, and Clay to mention a few. I will bring my AL37 with. they are an awesome flying Bird. You will love the graphics from Callie I have ordered many from them. I am going to Sun City and Phoenix for two weeks this month to see my Sister and my younger daughter, I do plan on going to the june flyin too.

[406PIlot]

Callie shipped out my graphics today! It's a bit windy today, but i'm itching to get this thing back in the air. I just can't believe how much I like the AL37. I am extremely surprised. Such a great flyer.

I can't say enough good things about this plane.

[GliderGuy]

406Pilot, yes all set up as per the manual. one thing I did do, to try out this flying season, is increase the flap travel by 20%. As I fly off grass, I'm hoping it will get the plane up sooner. At the moment, it takes around 250ft to take off, i want to see if I can get it off a bit faster.

Hi SF - Short field training I received years ago proved the book theory correct. Lift only increases to 10 to 15 degrees of flap. After that amount of flap, drag significantly increases and lift only increases a little more.

The shortest take off distance is achieved with 10 to 15 degrees of flap. Add more than that, and the drag hinders acceleration....you won’t clear the trees.

Also, stall speed only decreases a little with more than 10 to 15 degrees.

Your best bet is to set 10 to 15 degrees of flap on take off. This will get you in the air in the shortest possible distance.

Think about it....you ever see a commercial airliner take off with lots of flaps? Nope! They reserve lots of flap for landing....when they need the added drag.

A Cessna 152 may not even fly with lots of flap set for take off...especially when heavy and on a hot day. That huge amount of drag that happens with more than 10 to 15 degrees is a take off performance killer! This aerodynamic principle should apply to model planes, too.

-GG

PS - If you watch carrier jet launches, some birds have full flap. I can only assume the huge thrust to overcome the large drag is a compromise to achieve as large a margin above stall as possible. Any former or current Navy pilots to comment on the full flap configuration off a CAT launch? Acceleration is NOT an issue....LOL!

[GliderGuy]

Congrats 406P! Glad you like it.

I am up late....just finished putting the wings on after adding the extra carbon square tubing in the top of the wing wiring channel to keep the top thin skin from cracking over the motor mount area like my #1 AL37 did.

Did some detail painting, too, before tail and wings went on. Got the RF chokes on the ESC wiring under the battery tray.

Other than installing pushrods and giving her an all-over water base clear/satin Urethane anti-UV paint job...a range check + maiden on Saturday will happen.

Calibrated the ESCs and checked all servos functioning. Soooo close. Ready to get her in the air.

-GG

[406PIlot]

Well I got out today and did the maiden today. This plane is an amazing flyer. I have fallen in love with this thing!!! Did the maiden then put in another 7 flights on it. Touch and go wheelies machine!

Got a ton of compliments on landings. This plane makes it so easy. The look of it in the air is something else. It has a huge realisms factor...

Can't wait for my graphics to get here from Callie. Looks good in white, but once windows and everything are done it's going to be even better.

[Scale Freak]

406Pilot, yes all set up as per the manual. one thing I did do, to try out this flying season, is increase the flap travel by 20%. As I fly off grass, I'm hoping it will get the plane up sooner. At the moment, it takes around 250ft to take off, i want to see if I can get it off a bit faster.

[xviper]

Well my new AL37 is assembled and almost ready to go. I just need to double check travel on control surfaces and program my rates (high / mid / low). The book gives the exact same travel for high and low rates for all surfaces. Pretty sure that's a misprint of some kind.

I need to go back through this thread and see what other people are using for their rates.

I doubt it's a misprint. They are "recommendations" and initial trial and error as everyone has different throws for their planes, so it shouldn't matter what others use to fly their planes. This plane is so benign in the roll and pitch that one rate is a good starting point. When faced with this kind of information, one needs to use a little deductive reasoning and common sense. Since you have a TX with 3 possible rates, you can dial in the only given rate as "middle". Then you can dial in a lower rate and a higher rate.

[406PIlot]

406Pilot, good call. I had to wait almost 3 months to maiden my Al37, but the wait for prime conditions was well worth it. You don't want to test fly this type of plane and have to fight the elements at the same time. Regarding your question on rates, I have none set on mine, just the one rate and for me, its really no issue.

Are you just using the "high" rates as per the manual?

[Scale Freak]

406Pilot, good call. I had to wait almost 3 months to maiden my Al37, but the wait for prime conditions was well worth it. You don't want to test fly this type of plane and have to fight the elements at the same time. Regarding your question on rates, I have none set on mine, just the one rate and for me, its really no issue.

[406PIlot]

Was going to maiden today, but the wind ended up being a bit stronger than reported by NOAA and multiple other sources. So I ended up holding off. Weather is supposed to be better tomorrow so going to attempt the maiden in the afternoon. Hopefully the weather holds up so I can get this bird in the air.

[GliderGuy]

AL37 arrived today....that was FAST! Got the fuselage together, put the decals on and receiver/wiring done. Added the fuselage topside short carbon rod EXTRA bracing at the fuselage joint to help ensure the halves don’t come apart at the top on hard landings.

Put a small RF choke in the tail...running elevator and rudder wires through it. Secured the rear fuselage wiring so it doesn’t flop about. Then I added another small choke by the green toroidal ring. Since there is room, next step will be to remove the battery tray and install chokes on both sides of the ESCs. Overkill, but Bird #1 flew trouble free (radio wise) for 2,000+ flights with all these RF chokes. Not gonna mess with success.

Trying to have it ready by this weekend and the forecast good weather.

Tomorrow...Painting silver on the leading edge flaps area and the silver anti-icing on the horizontal stab’s leading edge. After that, I will add the internal carbon reinforcement to the wing’s wiring channel to avoid the top wing skin cracking I saw develop on Bird#1 on the motor mount area. Then final assembly, an overall coat of water base SPAR URETHANE, and I will be done.

My goal is a Saturday maiden.

-GG

[406PIlot]

Well my new AL37 is assembled and almost ready to go. I just need to double check travel on control surfaces and program my rates (high / mid / low). The book gives the exact same travel for high and low rates for all surfaces. Pretty sure that's a misprint of some kind.

I need to go back through this thread and see what other people are using for their rates.

Hopefully my graphics from Callie will be here by the end of the week.