Conference vmszoo::rc

We've had several AirCore planes flown at the Ware field. In talking to the 
owner, he had been very pleased with the performance and durability. They 
aren't a highly wingloaded as the Dura-series so they fly/land slower which 
is a plus when training.

    The trainer flys well but the bibe is for the much more experienced
    pilot from what I have seen. They are tough.
    
    E.

    Since my mid-air crash, one of my friend loan me his Aircore 40 so that
    I would have something to fly during my vacations. I whas quit suprise
    by the performance of the airplane. Althought you have very little
    control at low speed, the plane fly beautifully. I have been able to
    save my Royal 40 engine and although it run only at 3/4 of it's power
    it managed to pull the Aircore just fine
    
    The front wheel assembly is flimsy and had to be beef't up so that we
    would not have to repair it every tird flight. I also had to put a
    balsa support at the end and at the start of the pushing rods used for
    the rudder and elevator to prevent these flexible rod from bending.
    
    The plane is also a joy to clean after flights. Just a little bit of
    Windex and wipe it off you never worry about absorbtion into the
    material.
    
    The airplane turns well and comes down fast with no power but you can
    manage a loop with no problem and a roll if you have full travel on
    ailerons. Make sure the rear dowel to hold the wings is not in the way
    of the ailerons hardware. My friend did that and I had no aileron on
    the first flight. The plane is very stable and I have no problem making
    very low passes  with it.
    
    
    Jacques
    

     The NH is a regular at our field. The person who is learning to fly
    with it 
    has an OS 48 4 cycle on it. Saturday he landed in a tree with the
    engine still running. He just kept reving the engine till the wing came
    off an the whole thing came tumbling down. Picked it up, put some new
    rubber bans on it and started flying again. It just had a few scratchs on
    the wing and fuse, nothing to repair. He flys it as a tail dragger
    and is using flaps. He has also dumped it a number of times in the
    tall grass with no damage. It sure can take a beating and keep on
    flying.   Seems to be a good trainer for those that don't like to make
    repairs. Flys well too.

    Thanks for  all the timely input!
    Time to break into the piggy bank (again)
    
    rob

	I just completed the Knight Hawk. The assembly was like the old 
paper airplanes, You Know, Flod along line g and insert tab p into slot t.

	The plane flew O.K. but it likes to sink fast if the power fails.

	The only thing I didn't really like about it is the Glue you use is 
contact cement and you have to wait 30 mins each time you glue a part.

	Also the glue is NOT fuel proof and I have found that I have had
to re-glue the tail assy once already because the fuel residue finds its
way into the seams loosening the joints.




						Larry

    You can use CA to glue the parts together. I did it with the Aircore 40
    and it held OK.
    
    Jacques
    

	I thought of using CA but was afraid it would not work. I did use hot glue the
last time I had to reglue the tail section. This seems to work better.


					Thanks
					Larry

    After flying one of the Air Core models owned by one of our new
    members, I'm prompted to start a more probing discussion about this
    design.  On two different occasions flying the same airplane, the results 
    were so dramatically different that I thought they were two different
    airplanes.  SOme members of my club have also flown both this plane,
    and the same model owned by another member.  The reports I've heard
    lead me to believe that people either think this is a great plane or
    its one of the worst planes around.  How can there be such polarized
    views of the same plane?  Something is not quite right here.
    
    On the two occasions I've actually flown the same plane, the results
    were radically different.  One day, I couldn't control it or get it to
    fly right.  Next time it was a pussy cat!  WHy, I thought, could this
    be the case.  Is there something inherent in this design that is
    unstable from time to time, yielding varying results each time its
    flown?  I'm very curious about this.
    
    One theory I'm considering is that the _very_ pliable materials used in
    the construction can seek a different shape from day to day due to
    temperature, humidity, how it was stored, etc.   We all have
    experienced the trim problems caused by nyrods, and I think a plane
    made out of plastic might just suffer from the same problems.  Not
    sure.
    
    Does anyone else have any thoughts about this issue?  I'm certainly not
    trying to bash the Aircore products, just trying to come to grips with
    my vastly differing experiences, and the love-hate comments I've heard
    from others.  
    
    On the plus side, Aircore has done a swell job of creating one
    extremely rugged airplane that can withstand _and_ recover from
    tremendous abuse.  But has it also created an airframe subject
    to dimensional instability, making it difficult to predict how it will
    behave at any given time?
    
    Let the controversy roar!
    
    I may regret starting this.
    
    Cheers,
    Joe 
                                                 

    
    If one airplane would behave different, I'd say check the pilot. If one
    type of airplane would behave different where's the problem ?
    Everything could be different with different builders or even the same
    builder but multiple planes. I've had several occasions where I've
    flown exactly the same type of models but with contrary results. Take
    the Gremlins....
    I once had an experience with the CG a bit aft at a Super Sportster. I
    thought that from time to time I would have gotten interferences. 
    Many flights later I checked the CG - and had to add one pound of 
    lead !
    
    
    Bernd
    
    
    

     The construction of the fuselage uses varieing thicknesses of the plactic
and the instructions have you alternate the "grain". I have been flying my
Knight Hawk and it flew the same each time. I guess if someone didn't build
it using the alternate "grain" method it could flex a different way depending
on the temperature.

			Larry

If it was two different sessions then it's possible that the plane was 
either rebalanced or broken and repaired in between the sessions. CG will 
have dramatic effect on such a heavily wing loaded plane.

Many people just glue the tail back on without ever rebalancing. Weight 
out at the tail will have quite and effect.

    Referring to 1543.9,  I have a Corostar and so does another club member
    (he is also a DECCIE).  They are the WORST flying things I have ever
    flown.  Being that they are LOW wing planes, you can multiply the trim
    problems by 10!  They never fly the same way twice in a row.
    
    The original intent was to use these for combat, but nobody can fly
    them consistently.  We even tried to midair them, but they are all over
    the place so bad we can't even get close.  
    
    They do change shape and trim quite a bit.  The high wing versions are
    less prone to this I'm sure.  I gave up on mine and can't even give it
    away.  As the saying goes, "If they are designed to crash better than
    they fly, that is what they will do".  I learned to prefer planes that
    are designed to fly, not crash.
    
    
    Ultra Sports Forever!
    
    Ron

    Ron,
    	Get a Gremlin if you want a good flying combat ready ship!  They
    are low cost, easy and quick to build, and they fly like they're on
    rails.
    
    Charlie
    

    Charlie,
    
    I have been considering bringing the "Gremlin Wave" out West.  Isn't
    there a Gremlin note here somewhere??
    
    Ron

Topic 166 in the DECRCM notesfile (or email me for more info)

    As Jim Reith said, the Gremlin discussions are in the DECRCM file. 
    There are lots of them and we have had a ball flying combat with
    Gremlins.  We just had a combat contest with another local club that
    has also discovered the Gremlin.  It's a BLAST.
    
    Charlie
    

Word has it there will be a product review in the december issue 
of RCM and I believe there's a Christmas Special being offered by 
RA Cores if you read their ad...

    What's to review on a Gremlin? 
    
    You Build it
    
    You Fly it
    
    You have FUN!
    
    
    

    What's to review on a Gremlin? 
    
    You Build it
    
    You Fly it
    
    You have FUN!
	
    You overdose
    
    You crash it
    
    You fly it
    
    You overdose
     
    You crash it
    
    You fly it.......................No cure.   
    
    
                                             

    I've crashed more since getting into Gremlins - but all of my crashes
    have been Gremlins and most have been easily repairable.  The reason
    for more frequent crashes is that we have flown them ALOT!  We also
    tend to do things with them that you would not do with any other plane. 
    We fly them lower and closer together and in combat!  I have had at
    least 5 midairs over the last three seasons of Gremlin flying. (Wow -
    has it really been that long? )  I've retired three wings and lost one.
    I've only retired two fuses though.  I couldn't even begin to estimate
    how many flights I've made with the Gremlins.  I keep two flying - one
    with an OS25FP, the Combat version - and one with an OS32, the Sunday
    Version.
    
    There is no cure for Gremlin Addiction
    
    
    Charlie
    

    Gremilin addicts,
    
    Jim Reith sent me the pertinent info.  I will order a kit and see what
    I can do to begin a wave here.  I will keep it quiet and just show up
    with it one day. 
    
    Sounds like this US AIRCORE note should be renamed "The Western Gremlin
    Note", or would someone care to start a new Gremlin note for this con-
    ference for newcomers?????
    
    Thanks again, Jim
    
    Ron

Perhaps one of the moderators can move the Gremlin notes to a Gremlin 
topic and have both?

And then delete this reply as unneccessary

    Better yet, get one of your buddies to also build one then you both can
    go out and put on a show!  Actually, much of the fun flying a Gremlin
    comes from flying with another Gremlin either in formation or combat. 
    Formation flying is great practice for combat since you work to keep
    the two (or more) planes close together.  
    
    Charlie
    

    
    Can't help but think of the little guy in the Bugs Bunny Cartoons
    
    Huh-huh-huhuh-huhuhuh! <-- To the tune of "Yankee Doodle"
    
    -Ed
    
    

    Gentlemen,
    
    The first Western Gremlin will hit the road next week!  I will have to 
    "audition" it to the clubs as most of these guys are resistant to new
    things, but it will catch on.  Gremlin Combat will provide some cheap
    thrills they will like. 
    
    I have a terminal at home so I can access the Gremlin notes as I build
    if necessary. 
    
    What is the approximate speed with the OS 25 FP?  I have one as well as
    an ASP 40 available.  I doubt I would put the ASP on, but it's
    interesting to ponder.  It will pull a Scat Cat straight up for a
    looong time.
    
    I read the article in RCM about combat in Mass., GOOD JOB GUYS!
    
    Good landings,
    
    Ron

Ron,

It is possible to build a 25FP Gremlin with standard size servos at 
under 3 pounds. At this weight it will perform quite nicely. Covering 
adds 5-10mph to the speed. We're all using APC 9x6 props on the 25s. 
The 40 isn't really much faster but it will give you better torque 
for climbing. It ends up a little heavier and the more weight the 
larger it pushes the manuevers.

In the kit there is a frequently asked questions sheet that will give 
you most of the reasons why things are the way they are. The other 
note to read about the Gremlins in is the Skunkworks topic in DECRCM 
back in the early months of 1991 (if the housecleaning hasn't archived
them yet).

My 25 Gremlin is 2.75 pounds and quite lively. I have a ball with it 
"relieving stress" doing things I wouldn't attempt with a plane that 
was more expensive time and money-wise.

The directions have been updated several times since 1991 and 
incorporate most of the changes. Hints and suggestions can be submitted 
and will be posted in a newsletter.

    For combat I prefer the 25 but for fun flying I use an OS32 which is
    probably about the same power as the ASP 40.  I beg to differ with Jim
    but a good 40 will be much faster than the 25.  The 40FP is not much
    faster but it's quite a bit less powerful than a ball bearing 40.  Keep
    your Gremlins light and you'll love they way they fly.
    
    Charlie
    

No need to beg 8^)

Yes, I was comparing the 25FP with the 40FPs that I've seen. Most 
people I talk to have 40FPs on their trainer that they swap onto the 
Gremlin without too much added speed.

    Charlie, Dave,
    
    Referring to the 40/25 issue again.  Wisdom tells me to use my 25FP 
    first.  The reason I mentioned the ASP 40 is the altitude difference
    here, we are a mile high and higher in some places.  Thinner air means
    less power, but less drag for the prop and airframe.
    
    I have not seen performance figures comparing say sea level to a mile
    up.  I have heard horizontal speeds are similar, but what about ver-
    tical?
    
    Anyway, back to the ASP 40.  If I remove the 25FP and put in the 40,
    will the Gremlin allow me to rebalance the CG without TOO much prob-
    lems?  I know Eric put a YS45 in one, so it can be done.  By the way,
    did that one clock 200 MPH??????????????????????????????????300 MPH??
    
    Ron

    
    Ron,
    
       I am currently running a .32 with a pipe on a scaled down 3/4 scale
    Gremlin. Eric is running a .46 pumper with pipe on his aerodynamically
    cleaned up "full scale" version. They both go like stink, and have
    unlimited vertical. They are great, cheap, stress relievers, good for
    ducted fan training, but definately NOT for combat! (can you say
    shredded streamers, and :).
       Jim Reith and I both have "Twin" versions with dual .40FP's. 
       
       The point is, there are many Gremlin derivatives, but for combat, you
    can't beat 2 (or more ) .25 versions! If I had to keep just one
    Gremlin, it would be my .25 version.

    
    
      Ron,
    
        My experience is that they tend to balance BETTER with a .40 than
    a .25. Usually, the fuselage will need to be moved forward an inch of
    more from the back of the wing to get a .25 to balance.

    
    OK, so what you are saying is: BUILD TWO!!!!  I can live with that. I 
    will go the 25 first to get my feet wet and demo for combat purposes.
    
    Ron

They're cheap enough that you can build two and then you can swap 
parts if you need to keep one in the air. I like my .25 but the twin 
really gets the adrenalin pumping and it sounds real neat in the air. 
If I were to do another twin, I'd use .32s simply because the carbs 
are easier to adjust. The FP airbleeds are a pain to get adjusted.

Space the wing bolts the same and you can swap wings in a pinch. The 
balance issue resolves itself by sliding the fuselage front to back 
and drilling the bolt holes once it balances.

    Jim,
    
    By the way, will I get two wings like the RCM ad says.  I'm already
    thinking ahead............
    
    Also, what is the common, sucessful way to finish the wing.  I am lean-
    ing toward thin balsa sheeting and monokote for easy repair.
    
    Ron

Don't sheet it.

The durability of the wing is in the flexing. The sheeting adds 
unnecessary weight and makes the wing more brittle. I've got to run 
for now. More tomorrow.

re: .30 Ron: The short-lived Colorado Gremlin flew just fine at 7200
feet with a much used 1972-vintage OS25.  The worst I can say is that
it was a little touchy on launch.  But that could be that whoever was
helping me launch it was usually snickering as he threw it.  Turned to
WOWs after that!

Plenty of power...enough to stuff the damn thing through a fence, no
sweat.  

    I'd recommend building two!  However, it's easier to build two after
    you've had some building experience with the Gremlin.  Otherwise you
    might make all of your mistakes twice. :-)  I build two wings at a time
    now - it saves time.  While one is glueing I do the other.  If you want
    excitement, you'll like an overpowered Gremlin.  Dan Weier and Eric
    have the fastest Gremlins in the East!
    
    Charlie
    

    No one knows how fast Eric's 46 powered Gremlin really goes. We tried
    to measure it with a radar gun, but the gun was shattered by the sonic
    boom as the Gremlin ripped through the sound barrier. I'm sure Eric's
    next Gremlin (with what, a Hanno Special?) will emit an Electro
    Magnetic Pulse, lighting up control boards all over NORAD.
    

  Well I hate to be the bad guy here....but I have to say that Gremlins are
the worst thing to come along in r/c for the past 15 years!  I'm not joking
either!!  Do you know how easy it is to neglect other building projects so
you can go out flying?!?!  And why bother spending 200+ hours building that
new kit when a Gremlin can be built in a day??  

  It's just TERRIBLE!!!!!!

  On the other side of the coin though....I'm certainly keeping the propeller
manufacturers in business!!!!  :^)



            Jim (3 wings on the building board right now...)

         If Gremlim = neglect then I have 2 problems in the form of 2
    pattern birds I am building.  I have been working on one for 3 1/2 
    years now, so it won't mind much.
         So now I know at least one Gremlin is in Colorado.  But I never
    heard of a regular event of flying them into a fence?  Our club does
    that here, but ours are unscheduled!  However, I did manage to pull off
    a "maneuver" that I will bet NO ONE has done before.
         About a 3/8 of a mile away from the runway is an antenna tower
    with microwave dishes at the top (does not hit radios).  This tower has
    guy wires around it, of course.  I took my Four Star (SIG) and did a
    complete, seemingly eneventful, flight and lined up my appraoch to
    land.
         Before touchdown I (and others) noticed that the landing gear was
    missing!  That lead to a belly landing.  Earlier in the flight, I was
    close to the tower.  APPARENTLY I must have clipped one of the guy
    wires and ripped off the gear, but the plane never showed any
    deflection or abrupt changes.  The prop was undamaged.  TOP THAT!
         Lastly: Has anyone thought of a GIANT GREMLIN?  Maybe 8 ft
    wing???  Retracts??

Well, there's a few Giant Gremlins out there with 66" wingspans but 
nothing bigger than that currently. You got a G62 hanging around 
looking for a place to sit? Be real careful using a gas engine on a 
Gremlin. Gas dissolves foam quite nicely 8^)

    Eric had a Gruesome Gremlin that had a ST2500 on it.  It was pretty big
    - I don't know what the span was.
    
    Charlie
    

    I still say that we should build a full scale Gremlin...  Then we 
    could enter the Gremlin in scale competition..
    
    Now, if we could only find a pilot...   Maybe DW2 will come out of 
    retirement..  Or we could call Burt Rutan...  He flys anything...
    (Me??  well....  maybe it isn't such a great idea... :-)
    
    

    I want to see who's gonna launch a full scale Gremlin!  And I also want
    to see the first landing.  Full Scale props get expensive don't they?
    
    

Just make it a Fred Flintstone mobile and that will give the pilot 
the incentive to make a good landing 8^)

    How about doing what Evil did - put wheels on the top and a skid on the
    fins.  Takeoffs and landings inverted only. :-)  I saw a Pitts with two
    sets of wheels once.  The guy landed and took off inverted.
    
    Charlie
    

I busted a lot of props too, though mostly it was my own fault for not
putting them on right.  But I thought of adding a single wheel like
they did for free flight in the days of yore.

If you put on a single wheel then you tend to bang the elevons which 
bends the control rods which changes the trims... One of my customers 
put a set of dural gear on the rear bolt block and a nose wheel in 
front of the tank on a bulkhead they installed. I've found that if I 
land and drop one wingtip the plane will turn and slide sideways and 
kick the prop flat most times if I notice a hanging prop. Sometimes 
it still digs in and breaks but at least I feel I've made an effort 
to save the prop. 

    If you install the prop so that it is horizontal when it is against
    compression turning CCW, you will not break too many props if you kill
    the engine BEFORE landing.  I have had trouble with some engines
    getting them to stop quickly enough.  With the 25FP, it's no problem if
    you set the carb up to completely close.  You will get unlucky
    sometimes and have the prop stop vertical.  This sometimes results in
    a broken prop but if you do what Jim says and come in slowly and drag 
    a tip first, it will often keep you from breaking a prop.  Landing
    surface influences the prop breakage also.  I break most of my props
    flying into the ground on low passes trying to pop a balloon. :-)  I
    don't break too many on landings.  The fuel savings flying a 25FP pays
    for my props and then some.
    
    Charlie
    

    
       Sure, I'll fly the fullsize Gremlin, just let me know when it is
    ready! :). Don't laugh, but about 1 1/2 years ago, I started sketching
    out a ultralight size gremlin ( with wheels and single fin with rudder :). 
    
        I stopped once I figured out how big the drainpipe would have to
    be! :)
    
        A "stock" version could use a ROTEX engine, and the full size
    "Gremrocket" version would use a 300 HP Turbo Lycoming! :)
    
        Seriously, done correctly, a fullsize gremlin could probably be
    to the home built market ( cheap, easy to build, and good performing )
    what the current Gremlin is to RC. It would also drive the scalemasters
    guys crazy when we entered a gremlin! :)    
    
                                                               DW2
    
        P.S. If I DID fly it, I sure wouldn't mind one of those ballistic
             parachutes to be installes, like they now have for Cessna
             150's!

    Re: the past bunch
    
    Gents, aren't we a bit off this topic?  Not that I don't enjoy this
    discussion, but check the title.  Maybe the moderator(s) should
    get these into the Gremlin topic.
    
    -Joe 

That's what we need a fold up US Aircore style fuselage holding a 
person and a Rotax. NOW who's going to test fly it? 8^)

    Maybe I can dig up some old contacts to Rotax (who did the machining
    for the actuator motor on the European RA90 disk drives).
    
    When the magnet vendor found out what the main business of Rotax were,
    they joked that if we had given them a black box to design a disk drive
    actuator motor, they would have come up with a 2-cycle.
    
    Best regards,
                    Hartmut

    I'd want an Ejection Seat.  
    
    

    Does this file have a moderator now that AL R left. I know we have
    peopel who look after it but they don't moderate?.
    
    This was a DECRCM file until certain contributors and self appointed
    moderators refused to respond to the now dormant DECRCM BoD.
    
    Is it time to manage this file correctly now that the personalities have
    left Dec?.
    
    Regards,
    
    Eric H. Dormant DECRCM Pres.
                            

    Eric,
    
    For now why not just put the dialogue to note 1565 that you created.
    Then we can leave this US AIRCORE note be.

    This note has been idle for some time, and I am not sure what the
    conclusion was.
    
    Is the Aircore a good trainer or not?
    
    My son and I are learning to fly, and I seem to spend a lot of time
    doing major rebuilds on our Flair Cub. I am looking for a tough, easy
    to fly trainer so that we can graduate to solo before flying anything
    fancy.
    
    The Aircore trainer looks attractive, but I have heard a number of
    worrying comments:
    
    1) It is not very precise to fly, not as precise as the cub for example
    2) Very heavy, needs a much larger engine than they say
    3) Difficult to build, particulary folding the wings.
    
    So what is the verdict? Is it a good trainer or not? They are very
    expensive over here - #89 (ie about 1.5 x dollar price), so I would
    like some idea of whether they are a good bet or not.
    
    Thanks
    
    Stewart
    
    

    Like the duraplane, they are fairly rugged and will take a lot of
    abuse.  However, they can also quickly become heavy and warped by
    repairs and often will not fly the same two flights in a row!
    
    Before you change planes, lets take a step back..  Why are you doing
    major rebuilds on your Cub??
    
    Here in the states, most clubs offer quite a bit of training for new
    pilots.  It is usually only in the "learning to land" phase that a
    beginners plane will start to get banged up.  And while there is the
    occasional severe mishap on landing, it is usually no more than a bent
    landing gear or broken prop.
    
    Do you have an instructor?  If not, get one!
    
    I do not recommend US Aircore planes..  Folks around here have had
    very good luck with the Thunder Tiger and Hobbico trainers.
    
    Cheers,
    jeff
    

    
    
    
    
       I  agree with what Jeff says ( God, that's the second time this
    week! :). I have flown a few Aircore planes, sometimes they fly great,
    other times they are a handful. I can't speak to the building part, as
    I have never built one.
    
       Your money would be better spent buying a good trainer ( ie;
     Thunder tiger, Flightstar/Avistart, PT-40, etc ) and a buddy box.
    
       Once you have these two, get a good instructor. It will make for
     a much more enjoyable, quicker, and cheaper route to success!
    
                                                    Good Luck,
    
                                                          Dan
    
    
       

    Thanks
    
    For some reason buddy boxes are not encouraged in our club. The chief
    instructor seems to take the view that they are not condusive to taking
    full responsibility for your plane. The instructor who teaches us most
    of the time would use a buddy box if I had one. However over here it is
    difficult to get hold of one, and the alternative is to buy a second
    full transmitter (which is expensive when you are starting out).
    
    Following the accident last week, I am going to try to change the
    attitude to using buddy boxes in the club, but you appreciate that as 
    a new boy on the block it is difficult.
    
    Here is what happened - my son was landing. A couple of feet off the
    ground, and about 1/3 up the runway a gust of wind caught the plane
    and lifted it off the ground, towards the pilot line. One stepped out
    of the way, one ducked, and the instructor grabbed the transmitter.
    By this stage the aircraft was heading for the pits at chest hight
    (actually straight for me). It crashed (or probably was crashed) about
    20' in front of me. 
    
    However I need to seperate the politics of getting the training and
    safety policy changed from the issue of getting a good trainer in the
    air again. It sounds as if Aircore is not to be recommended, mainly due
    to its inconsistency. 
    
    Stewart