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Nitro models pusher Bobcat?

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Old 11-27-2007, 10:14 PM
  #2626
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Default RE: Nitro models pusher Bobcat?

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I come in at a rather high AOA, and hold it as much as possible, but short of adding brakes or landing on grass, there's no way mine will stop that quickly.
Long landing roll out can easily be fixed in less than 5 minutes at a cost of less than 10 cents and can be undone in less than 5 minutes if you don't like the solution.

Slip a short piece of tubing over the wheel collar and against the rim on the mains. Adjust for a very slight mount of friction. Landing roll will be cut in half. I have four airplanes that I occasionally land at a very high speed that have collars to prevent excessive roll out.

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Old 11-27-2007, 11:11 PM
  #2627
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Default RE: Nitro models pusher Bobcat?


Quote:
ORIGINAL: BillS

Long landing roll out can easily be fixed in less than 5 minutes at a cost of less than 10 cents and can be undone in less than 5 minutes if you don't like the solution.

Slip a short piece of tubing over the wheel collar and against the rim on the mains. Adjust for a very slight mount of friction. Landing roll will be cut in half. I have four airplanes that I occasionally land at a very high speed that have collars to prevent excessive roll out.

Bill
I had thought about doing that too, and given that the plane seems to push forward at low idle this may not hurt takeoff performance either.

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Old 11-27-2007, 11:20 PM
  #2628
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Default RE: Nitro models pusher Bobcat?

Bad Week last week

I was flying in about 20 knot winds 2 weekends ago... I was doing 125 mph upwind passes low on the deck...pulled up rolling.....and flamed out! Totally my fault for leaning it out too much...

so I was about 30' up....dead stick, 20 knot wind, and I'm right over the end of the runway...dammit....OK, relax....I got it turned downwind....no elevator - it stalled....I let it go until about 15 feet, and had airspeed to get it level. Dropped the retracts, hit the spoilers....made it within 6 feet of the runway....looked like I was still going pretty slow and nose high, mains hit the grass first...RIIIIIIIIIP! Dammit, ripped the mains out of the bottom of the wing. Top looks fine, although a stress crack in the Fuse, and the canopy cracked.

I'll get it fixed and back in the air by next week, but I'm bummed out - it's not "virgin" any more. I've been flying the poo out of my bobcat, and it's killer! I don't take the entire runway to land, and I've realized that it handles well at very slow speeds if you manage the throttle correctly.

I just bought the Cessna 310 (Top Flight) Twin - 2 OS 55 AX's - but I have not opened it up yet until I get the Bobcat back in the air. Should be flying this weekend, if I can find a canopy - Nitro Planes says 3-4 weeks! Anyone want to sell a White one, or know of a clear one for sale that will work?

Thanks,
MarK
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Old 11-28-2007, 12:11 AM
  #2629
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Default RE: Nitro models pusher Bobcat?


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ORIGINAL: caiman

NM Mark,

But it didn't felt like it had no climb rate with the 46FX? what fuel were you using with the 46FX?

On your 150ft landings did you have flaperons programed?

Thanks.
Climb rate was lousy with the 46 - I had to work it much like I did with my ducted fan
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Old 11-28-2007, 01:59 AM
  #2630
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Default RE: Nitro models pusher Bobcat?

I couldn't tell you how many feet mine used to run out but what you guys say has some merit. I'm using spoilerons as well but I have no down elevator to compensate for the spoilerons so it brings the nose up nicely. This has allowed me to come in at a slower speed with a higher throttle setting which makes the plane much more stable, at least it seems much less pitch sensitive.

I wonder if CG is playing a role in this, I run at 10.3" which by my testing is on the ragged edge and before the spoilerons I had to psych myself up for the landing and it ran a long way.
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Old 11-28-2007, 06:05 AM
  #2631
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Default RE: Nitro models pusher Bobcat?

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Climb rate was lousy with the 46 - I had to work it much like I did with my ducted fan
I am considering a .46? Do you know the all up weight?

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Old 11-28-2007, 06:56 AM
  #2632
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Default RE: Nitro models pusher Bobcat?

BillS - If you're going to buy a motor, get the 55 AX - same mounting pattern as the 46, but the power of a very strong .60.

I run mine on 30% heli fuel - (broke it in with 1 gallon of 15% first), APC 11x7 Pusher Prop, Jett tuned pipe - I"m turning over 14,500 on the ground. I get clocked regularly over 130mph. And yes, it's the retract model.

1/4 UP spoilers, with about 8% of down elevator mixed in allows me to drop my gear and hit the spoilers and the plane just slows down and settles in with a nose-high attitude....then you need to manage the throttle properly, but you can land with a fairly short rollout - not like landing an Extra, but I also don't take up a 600' paved runway....maybe 1/3 of it with the spoilers....without them, yeah, it's a rollout.

Cya
Mark
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Old 11-28-2007, 08:28 AM
  #2633
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Default RE: Nitro models pusher Bobcat?

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BillS - If you're going to buy a motor, get the 55 AX - same mounting pattern as the 46, but the power of a very strong .60.
I have the airplane on order from TexasRCPlanes. Cost plus shipping to NC was about $121.
http://www.texasrcplanes.com/bobcatjet.html

I have the following engines that are not in airplanes.
OS .46
TT .46
OS .50
ST .51
OS .61
ST .90
and a few others.

Don't have a clue how the airplane might fly for me. Purchasing another engine doesn't seem like a good decision.

Bill
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Old 11-28-2007, 08:57 AM
  #2634
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Default RE: Nitro models pusher Bobcat?

Use the .61 - the .90 will be heavy, and you're limited in prop sizes - unless you can rotate the front so it can run in the opposite direction - so unless it (the .90) likes to run at very high RPM, you're just adding weight that needs to be countered with nose weight. I added NO weight to mine with the 55. The 61 will make it go pretty well and will be lots of fun to fly.

I just bought the Cessna 310 from Top Flite - I read all your posts (speculation) before the plane came out - the wing loading numbers scared me, too, but after seeing vids with 46's flying it, I feel much better. I've already purchased 55's for it, and again I'll run 30% - the motor REALLY likes it and it makes a significant difference. Did you ever end up buying one for yourself?

Mark
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Old 11-28-2007, 10:10 AM
  #2635
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Default RE: Nitro models pusher Bobcat?

The ST .90 has a removable front housing but I have no experience running engines backwards. Agreed that the ST doesn't seem to be the correct engine for the airplane.

The Cessna 310 is a very pretty airplane but the wing loading was frightening. However a friend put OS .55's on one and has 10 or so successful flights. The landing speed calculated to be above my skill level. You probably won't have any difficulty.

Another friend has a beautiful Bob Cat that was flown once with a 10 pound thrust turbine. The weight without engine and servos is 7 pounds 9 oz. The wings were sheeted and the airplane was painted.

Bill
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Old 11-28-2007, 12:33 PM
  #2636
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Default RE: Nitro models pusher Bobcat?

i order the spring air retracts #302 , i have the retract ready bobcat, is there any changes i have to make on the bobcat,they say they fit perfect.
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Old 11-28-2007, 01:09 PM
  #2637
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Default RE: Nitro models pusher Bobcat?

BillS, you sure the ST 90 has a removeable front housing ?
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Old 11-28-2007, 02:09 PM
  #2638
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Default RE: Nitro models pusher Bobcat?

The old original ST 90 has a bolted on front case the new Chinese one definitely does not. I have both.
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Old 11-28-2007, 04:03 PM
  #2639
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Default RE: Nitro models pusher Bobcat?

So Bill - it's EASY. Just unbolt, and rotate 90 degrees. Bolt it back on. Plug in your started red-to-black (opposite) and start her up! (Don't forget to put on a pusher prop).

I still think the 90 is just too much weight, however (when you account for adding matching weight to the nose to balance it).

HappyJack flies at my field, and he's got a Bobcat 52 with Turbine mounted up on it. Looks REALLY cool - I haven't seen it fly yet, but I'm hoping this weekend I'll see it and maybe even get some stick time with it.

Here's my thoughts: Turbines will make it go faster. Turbines sound really cool. But they are not for me: too expensive, too many safety/AMA hurdles to jump, and you have to carry around a TON of fuel, which makes it a heavy heavy airplane. I'm sure it flies fine, but must be tougher to fly than mine.... I just can't justify it, and have better things to put my money into. (My humble opinion).

OK, I'm off to the hobby shop to donate more money to the cause!

Does anyone know where I can buy a Bobcat canopy? That's what's stopping me from getting back in the air, dammit.
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Old 11-28-2007, 04:43 PM
  #2640
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Default RE: Nitro models pusher Bobcat?


Quote:
ORIGINAL: marktur

Does anyone know where I can buy a Bobcat canopy? That's what's stopping me from getting back in the air, dammit.
My wife picked up something from the store last weekend.

It had bubble packaging about the size ( actually oversized ) of two Bobcat canopies.

I immediately grabbed it.

There was an article on either the AMA's magazine or RC Flyer on how to use a heat gun and a simple wooden "form" to work the bubble packages into a shape which you may need for a canopy.

I haven't tried it, but it looked quick and easy.

Basically you put on a glove and heat the plastic until it is soft, then you use the glove to shape the plastic over the form, achieving the shape you want.

After seeing the article every plastic package I run accross now becomes a potential canopy.

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Old 11-28-2007, 04:46 PM
  #2641
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Default RE: Nitro models pusher Bobcat?

I dont know if same materials are used for soft drinks bottles in USA but in UK they can be shrunk quite readily around a woodden plug by application of heat from covering hot air gun
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Old 11-28-2007, 05:21 PM
  #2642
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Default RE: Nitro models pusher Bobcat?


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ORIGINAL: davej78

I dont know if same materials are used for soft drinks bottles in USA but in UK they can be shrunk quite readily around a woodden plug by application of heat from covering hot air gun
That's right!

Even better.

That should work very well, as it is made to be maleable to obtain the bottle shape.

And you have some "pre-tinted" options too.



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Old 11-28-2007, 05:54 PM
  #2643
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Default RE: Nitro models pusher Bobcat?

Well, if I have to go through all of that, I think I'll just look for a canopy that's bigger than I need, and cut it down. I imagine the P-47D Bubble top or P-51D canopies will work fine, too, and there's nothing but glass there...so I will finally get a clear canopy afterall.

Are there any other companies besides Nitro Planes selling this model?
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Old 11-28-2007, 05:59 PM
  #2644
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Default RE: Nitro models pusher Bobcat?

I have a hard time thinking that the nylon screws are going to hold that tail on that fast of a plane, are you guy's using steel screws, or do you recommend the nylon? I bought Hi-tec HS-81 servo's for the rudders & elevator, are these servo's going to do the job? Thanx in advance for the input. Steve.
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Old 11-28-2007, 06:06 PM
  #2645
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Default RE: Nitro models pusher Bobcat?

www.texasrcplanes.com They may be able to help you. Good Luck. Steve
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Old 11-28-2007, 06:37 PM
  #2646
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Default RE: Nitro models pusher Bobcat?

marktur,
If your original canopy is only cracked, use some clear packing tape on the inside to mend the crack. I did this on mine and you can't even tell unless you are 12" from the plane.
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Old 11-28-2007, 06:39 PM
  #2647
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Default RE: Nitro models pusher Bobcat?

airhog1391,
DON'T use the nylon screws for the tail or the booms, replace them all with steel. The HS-81's will work but all those tail servos are a PITA in my opinion. Go back to page 99 post 2461 for a look at an alternate set up.
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Old 11-28-2007, 07:19 PM
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Default RE: Nitro models pusher Bobcat?

I wish I would have asked you this about the servo's before I spent $70.00 on mini's, I have about 30 reg. servo's laying around. I like the idea of only 2 reg. size servo's. Do you happen to know the size & thread of those nylon screws that I need to replace.
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Old 11-28-2007, 10:52 PM
  #2649
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Default RE: Nitro models pusher Bobcat?

Guys,

I will be receiving my Bobcat this week. After reading all the threads I could find I still have a couple of questions.

First, I thought I saw a post where someone ran their exhaust down through the wing to the bottom. Is that possible and how is it accomplished? Does anyone make a muffler for pushers?
I hate all the goo that assocoated with glow and I'm sure this plane gets coated with the exhaust blowing forward into the wind.

Second, I see a lot of guys using the Tower 75 engine. Would the AX 75 produce more power? Would it be worth the extra $$$

Thanks,
mike

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Old 11-28-2007, 11:11 PM
  #2650
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Default RE: Nitro models pusher Bobcat?


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ORIGINAL: nrthwing

First, I thought I saw a post where someone ran their exhaust down through the wing to the bottom. Is that possible and how is it accomplished? Does anyone make a muffler for pushers?
I hate all the goo that assocoated with glow and I'm sure this plane gets coated with the exhaust blowing forward into the wind.

Second, I see a lot of guys using the Tower 75 engine. Would the AX 75 produce more power? Would it be worth the extra $$$

Thanks,
mike

Hmm...

I answered this question in the other thread where you originally posted it.

But:

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