RE: Nitromodels PREDATOR RQ-1B
 

PappaJeff,

I started putting some of the pieces together on my Predator, and I found that the cut outs for the wing servos are very different from left to right. I could see where to cut through the covering and proceeded to cut out the opening. I soon realized that the left wing opening was way to close to the leading edge. The left wing opening is 3/8" from the LE, and the right opening is 1 1/16" from the LE.

There is no way a servo would have the depth needed to fit the left wing.

Is this a manufacturing defect? Were both you cut outs in the same place? I will have to make a new cutout by extending the hole toward the center of the wing and fill the part close to the LE.

Approach,

Not sure why you would want to add 5 inches to your wing, but I would not do it.

RE: Nitromodels PREDATOR RQ-1B
 

I believe these planes are know for having the wings fold up if a lot of airframe stresses are applied (see severla earlier posts.) Adding wingspan would certainly be likely to increase that risk.

As the previous poster said - why do you want to do that?

RE: Nitromodels PREDATOR RQ-1B
 

Yes, I think you have a manufacturing defect. The cutouts in the wing of my Predator were symmetrical, but not really deep enough for a small 9g servo. I ended up using HXT900's ($3.50 from Hobbycity!!), which seem to work fine (they are similar to HS-55's). They do protrude a little from the wing, but unless you look closely, no problem.

So, I guess you are stuck with trying to return your plane, or undertaking minor surgery! Good luck either way...Chris

RE: Nitromodels PREDATOR RQ-1B
 

Hi Chris,

I am also using the HC 9gram servos. I sue them in almost all my small planes. They did fit in the one wing half, and as you said only stuck up a hair, so no biggie. I already cut the other wing to place the servo in the same location. I can't imagine how they can make such a big mistake, as they are assembly line made.

I just finished up fabricating my nose wheel steering. It has shock absorber type hook up to save the servo in case of sudden shock to the landing gear. I hope it works.

Is the V-tail hooked up to rudder and elevator with mixing like an Elevon set-up. I am familiar with those, but never used a V-tail before.

Randy

RE: Nitromodels PREDATOR RQ-1B
 

Yes - the receiver's rudder and elevator channels are hooked up to the VTail, and you select the correct built-in logic. I am using a DX6i, and it works fine. However, I would really like to know how your steering will work - can you elaborate on the programming, and perhaps some pictures Very much appreciated!...Chris

RE: Nitromodels PREDATOR RQ-1B
 

Captain "Pappy"

It seems that your Predator's wings may have been assembled on a FRIDAY!
You did it right by modifying the servo openings and using some slightly smaller
servos. Initially, when the first Predators came on the market, there was an
issue of the wings folding under the stress of some high speed dives and other
high speed manuevers. This is why I choose to try the magnets and then decide
to go with the nylon bolts. Just remember that the Predator is made to be flown
in a very scale-like manner. Nice easy turns and leave the 3D and "need
for speed" runs for the appropriate style of planes. Ohhhhhhhh.....Yeahhhhhhhh!

RE: Nitromodels PREDATOR RQ-1B
 

PappaJeff,

Yep either a Friday plane or building after Happy Hour like me. The mod was easy enough, I just wondered if anyone else had the same issues. You would think after making hundreds of these they would be using some sort of jig for the placement of mounting holes.

I liked the Predator for it's Kool factor, and I love sailplanes, so a perfect plane for me to play with.

Chris,

I will get some photo's later today of the nose wheel steering set up that I hope will work.

As far as wing attachment goes, I plane to put in some magnets when they arrive, but had another thought:eek:

Why not put a small carbon fiber rod in the bottom of the fuse at the mid point and put a small carbon rod stud in each wing. Then just use a rubber band to hold them tight to the fuse.

Actually you could just use the studs in each wing, and make them at a slight angle outboard (to prevent them slipping off). Then use one rubber band to stretch across the bottom of the fuse and hook on to each wing. Me Likey that idea:)

RE: Nitromodels PREDATOR RQ-1B
 

Chris,

Here are the pics as promised. It is a little unconventional, but may work. It would be better to have the wheel turn like a car, rather than the sweeping motion, but I had this in my head, so I just did it. I did not want the wheel going straight down from the point where the reinforcing ply is in the fuse. Also figured to keep with the correct placement of the wheel in relation to the nose.

I'll let Y'all know how it steers

Randy

RE: Nitromodels PREDATOR RQ-1B
 

Spring shock absorber is interesting.

RE: Nitromodels PREDATOR RQ-1B
 

Yo Randy - Thanks for the pix etc - very interesting. I like the fact that you isolated the servo from the gear, and shock-loaded it.

My only consideration might be that the pivot point for the front wheel is behind the wheel's position - i.e. on landing, any oblique shock to the wheel might tend to make it (try to) veer to the side, as opposed to having the pivot point ahead of the wheel, (as in a castor on the bottom of a chair,) which would tend to go straight. Your arrangement does have a nice scale-like positioning for the nosewheel, which looks great!

So now my followup question is, how will you program the nose wheel? I've been thinking about it, and using a V-tail mix in your radio uses the rudder as an elevator as well as a rudder. So, if you were to connect the nose steering to the rudder, you would also affect the steering position when you operate the elevators, as well as when you use the rudder. I'd like to know the way round this so I can do it!

Thanks again...Chris

p.s. The real Predator B has retracts!! Anyone want to give it a try?

RE: Nitromodels PREDATOR RQ-1B
 

It is unconventional, but the nose steering on my Predator (post #597) functions with the ailerons. Yes, crazy, but it works fine.

RE: Nitromodels PREDATOR RQ-1B
 

Chris,

You are correct about using the rudder for steering, while also using a V-tail. I don't know of a way around that problem other than as
Jumper says to use the aileron channel to steer. I think it would be OK for light steering on the ground. I just want it to keep on a straight track for take off. On landing while keeping the wings level the wheel would be turning of course, but as soon as I touch down, I would let off the controls and let her roll to a stop. I will do the ground testing and let you know how it goes, but I will do as Jumper has done to start with.

Also, when using the ailerons in the air, the wheel will be turning, so I would imagine a small amount of drag as the wheel turns from side to side.

I had another thought:eek:

What if I just touch down on the main gear, and keep the nose up like on the Shuttle landing, then just ease the nose down real gentle.

Yea, like that will happen:D

RE: Nitromodels PREDATOR RQ-1B
 

Capt Randy - I don't think your nose wheel turning in the air will present a noticeable change in drag. By the way, the only way my Predator has flown is with fixed nose gear - the landing had to happen the way you describe (shuttle style). p.s. So far it has only had one flight.

By the way, I bought a pair of tiny xenon strobes and power supply from:

http://www.ramrcandramtrack.com/index.html (product RAM42)

- they really are very bright, and I may try to put them on the Predator's wings, as it is quite hard to see in the air (plus, turning them on during a fly-by will be pretty cool!) They are supposed to use a 9V battery, but I tested them and the 6V output from a separate UBEC seems to run them fine. I calculate that if I install them with a small UBEC and a Tedani relay, it will add 2.6 ounces, but I will be able to switch them on/off using a spare radio channel.

Any thoughts?

RE: Nitromodels PREDATOR RQ-1B
 

Chris,

The lights sound cool. Hope they work out for you. I was looking at the nose wheel again, and I might just change it to straight down from the bushing, so that the wheel turns on it's axis. It would be less likely to turn if slightly off center. It would be further back than it is now, but may work better.

It seems that I need to use my 1800 lipos to get the CG correct. I'm not done loading the servos, RX, and ESC, but it looks like a 1300 will be to light to achieve proper CG.

What size battery are you using?

RE: Nitromodels PREDATOR RQ-1B
 

Mine takes 2100mAh - 2200mAh. All the way forward, if memory serves.

RE: Nitromodels PREDATOR RQ-1B
 

Batteries - I use just the very forward section for a battery compartment, and find that if I parallel a 1300mah and a 1000mah in there, they fit in nicely, and the cg is currently fine. Apparently it is fine to use slightly dissimilar capacity batteries in parallel.

When/if I install nose steering and/or those xenon strobes, I expect the cg will be further forward, so I may just use one 1300mah, or two 1000mah's. At 15/25C that gives me a (theoretically) comfortable 21+ amps, which is about all I use at full throttle (little Chinese 'RC1200' outrunner and a 9x7 3-bladed counter-rotating prop - about 230 watts.)

All this talk is making me ready to fly! I live in Norwalk CT and the weather has been very unhelpful. Tomorrow should be above freezing and low wind - I think it will be a day to (try and) practise with my new Eratix! WooHoo.

RE: Nitromodels PREDATOR RQ-1B
 

To all with knowledge about the Predator RQ-1B, I address the below to the knowledgeable Papajeff but I would love anyone's input.

I'm a 30 y/o Criminal Justice student with a work history in the military (Airborne Infantry) and in law enforcement. I'm a smart, have plenty of patience, and no time limit to build this.

I want to put a camera (with both horizontal and vertical movement) with a video transmitter and a Range Video OSD (http://www.rangevideo.com/index.php?...roducts_id=135) with the regular equipment.

With all that said:

Papajeff,

It is because of your great thread that I bought the Predator as my first plane. I may have overstepped my limits but I wanted to get one before they stop selling them. I want to build it strong, both physically and mechanically, plane that will be able to carry all the required equipment and a few others. What would you put on the plane, now that you have had it for almost two years? I'm speaking mechanically. Would it be a more powerful motor, a stronger receiver, or a better whatever? Please help me with this. I want to do this right the first time through. I'm not looking for the best stuff, I'm looking for the right stuff. No pun intended. I'm coming to this thread with with an open minded and a warm heart.

Thank you,
Willis

RE: Nitromodels PREDATOR RQ-1B
 

Jumper - For a moment I thought that the white plastic pipe in your picture was actually some kind of sophisticated internal plumbing in your Predator, presumably pumping hydrogen peroxide to an army surplus torpedo motor in the tail. Then I realized it's just part of the missile insurgent-targeting system for the two JDAM bombs under the wings ;)

RE: Nitromodels PREDATOR RQ-1B
 

I could tell you what those secret pipes really are, but then I would have to ........well, you know.

RE: Nitromodels PREDATOR RQ-1B
 

I have been flying my predator for over a year now with the extended leads on 72mh with a Burg 7 receiver flawless so far. I am making the change to 2.4 now.
Freddy

RE: Nitromodels PREDATOR RQ-1B
 

Jumper,

OK, so I should be good with the 1800's or 2200's as far as weight goes. I would rather add battery weight, than lead weight.

Chris,

I'm not sure about using two different capacity batteries. There is probably a lot of discussion on that somewhere. You are doing that because of physical size, and the angle of the forward hatch, correct?

I am from Long Island, so I do remember cold, Brrrrrrr. Get out and fly. You need the Fix:D

Wow, you guys really know your weapons.

OK, off to work on the Predator

RE: Nitromodels PREDATOR RQ-1B
 

The original configuration of my Predator was 2100 - 2200mAh's with about 1 oz of lead up front. With alteration to nose wheel steering, the dead weight of the lead was no longer needed. Yes, still using 2100 - 2200mAh lipo's.

RE: Nitromodels PREDATOR RQ-1B
 

Yes - two batteries because of the convenient small space at the front of the plane. Also gets the battery weight RIGHT up front. I found that one 1000mah and one 1300mah seemed to get the cg perfect. I suspect that 2x1000's or 2x1300's would be close enough too.
Four good flights with the Eratix today!!! Frigging cold though.

RE: Nitromodels PREDATOR RQ-1B
 

junkjet, no going back once you have gone to 2.4.

RE: Nitromodels PREDATOR RQ-1B
 

Texas Willis,

Ohhhhhhhh............Yeahhhhhhhhhhh, Brother! Thanks for the kind words and I appreciate your interest in
the Predator. I am really pleased that this thread has lasted so long and has generated a lot of concepts
and ideas regarding this unusual UAV. I would strongly suggest to consider using the Spektrum 2.4 system
as it sure has become the wave of the future for RC. With just the Spektrum 6100 receiver, I have been
able to fly my Predator beyond the limits of my old eye sight and never a problem! For your setup with
the additional camera equipment, I would suggest to go for a larger outrunner, some where around 350
watts if the size is right in order to fit within the rear cowl. My motor was about 250+ watts and is just
fine for my "scale" (nice and easy) type of flying.

Also, I would use an appropriate size ESC for your larger wattage motor, and maybe consider using a
BEC, like the Castle CCBEC. A regular (tractor) APC 9X6 SF prop should work just fine, (as long as the motor is
rotating in the normal direction and is mounted with the little hub numbers facing to the rear), with your larger
power setup. I did not go with a stearable nose wheel and have not had a problem with takeoff's, yet I might
reconsider doing it in the future. Let me know what you have decided to do with your Predator and never
hesitate to post any additional questions or comments that you may have. We all, are willing to help in
any way. Hope to hear from you soon.