cmjets

Hey friends:

I find this video of a Htspot with NAVY bobcat scheme, really look very pretty. I am looking for a diferent scheme for my new Hotspot and the NAVY grey looks great.

http://www.youtube.com/watch?v=eoN9sX77vWc

BR from Spain.

Carlos Márquez.
________________________________
http://cmjets.blogspot.com.es/

mr_matt

My Feedback: (10)

That is also the world record, faster that the Olympus powered Firebird. Congrats!

iiievolution

Hello

Yes I was a bit surprised too with the 555 km\h, but mine is quite light, with no speed brake and no glasscloth\paint. Also on that day it was very cold for Cyprus. Only 6C, so the turbine must have been performing better.
As I sed, around 480km\h is what I will usually get on a normal flight, but I have struck the odd 500 + km\h every now and then.

Paul

iiievolution

Hi Matt

No I think that was a little bit faster and also I think that for the world record to be eligible you must have a conventional shaped aircraft, with main wings, tailplane, fin and rudder ( I think ) . Anyway the fastest RC plane is the scout. I have heard of speeds clocked at 680km\h [&:] . There's a vid on YouTube with one in the Netherlands.

Paul

cmjets

Hi Hotspot lovers:


more videos...

http://www.youtube.com/watch?v=qZAx6F6M5QM

http://www.youtube.com/watch?v=VzOvRV5bCDw


enjoy

Dr Honda

My Feedback: (4)

Thanks for posting that carlos.

I've see the second vid before. I think when my Hotspot is up and flying again... I'm going to put vector thrust on it.

taildragger21

My Feedback: (197)

Hey guys.. I will be recieving a used Graupner hotspot with a AMT 180 soon.. Looking forward to it!

mauryr

I have one flying too, powered by a changesun 120mm edf. Probably the cheapest flying hotspot of all times... Costed me less than a habu 32.
Maiden:
[youtube]http://www.youtube.com/watch?v=jF6lLmeqS-U[/youtube]

f4j race
[youtube]http://www.youtube.com/watch?v=x_qM_BK14Xo[/youtube]

Training
[youtube]http://www.youtube.com/watch?v=ksfHMW0yCj0[/youtube]

It's not the fastest plane ever, but it handles incredibly well.

One thing I found out about it is it enters an unrecoverable deep stall when flyinginvertedat low speed. Probably due to the profile of the wing.
Mine did the same as the one in this video, with much less thrust than this guy had, all I could do was keep the motor at full throttle and land reversed. Very minor damage reported.

[youtube]http://www.youtube.com/watch?v=VzOvRV5bCDw[/youtube]

Did anybody else experience this situation? How do you avoid it, other than avoiding slow inverted flight?

BaldEagel

The Rookie does not suffer from this, Possibly this is down to the canards coupled to the elevator, it may be possible to retro fit them onto the hotspot.

Mike

mauryr

Yes, fitting canards shouldn't be an issue.
Would it fix the problem though? What changes in the aerodynamics, other than the increased control throw when coupled with the elevons?

Thanks

BaldEagel

C of G has to be moved because of lifting force of the canard, it also gives better control over the attitude when used with the elevons, but decoupled and used as an air brake enables much shorter high alpha landings.

Mike

mauryr

And regarding the deep stall problem when flying reversed, do you think the simple increase of attitude control could overcome it and allow for a recovery?

BaldEagel

I would think so, but the Rookie II has a longer nose as well that increases the moment arm, if I remember correctly the hotspot had the canards fitted at a model update.

Mike

mauryr

I think you might be confusing it with the harpoon and the harpoon 2.

Fitting canards is probably a good idea for low speed aerobatics, while it probably isn't for high speed flying. In my case, there can't really be any high speed while EDF, so it would make perfect sense.
Thanks for the suggestion. I think I'll consider it against 1 or 2 axis vectorial thrust and decide for one of the other.

erbroens

Canards are useless at deep stalls, because they are stalled too. If you want to get out quick of "deep" stalls situations inverted or otherwise, the best way to do it is having thrust vectoring.

In the Video, this friend of mine was about to demonstrate a low level hover with his HS, and it was in control at all time. It only hit ground because it went below the power curve due to the extreme humidity and temperature of Manaus, in the Amazon where this jet meeting happened.


In regular Hotspots, without thrust vectoring many rookie pilots entered flat spins (inverted most times) and crashed because they tried to get out of it with power. The way for getting out of this is chopping throttle and letting the plane get out of it by itself, but this demands some altitude.

BaldEagel

Yes could be correct on the stalled canard, I have thrust vectoring on my Rookie so the deep stall is easy to get out of.

Your right I did get this confused with the harpoon however the canards at high speed are just as effective, in fact it makes the Rookie more responsive and smoother in flight.

Mike

mauryr

Well, when it happened to me I did have some altitude (the plane entered deep stall at the top of an aborted inverted looping, soon after I leveled it, by going back inverted all by itself).
The plane was not in a flat spin, it was just falling like a leaf, in a nose up attitude (looked like 45 degrees). I tried full throttle, no throttle, down elevator, up elevator, full aileron deflection. Nothing would change its asset much. I guess if I had enough space, with full throttle and full up elevator it would eventually have picked up some speed and elevator authority, but since I was going too far I just opted for an emergency inverted landing with full throttle and full down elevator.
This happened after I had been moving the CG back for a few flights, to try and compensate for the substantial down elevator required to maintain inverted flight, which was undesirable for aerobatics. The plane was flying well and didn't show any tendency to stall in normal flight, but maybe the asymmetric profile can cause issues with a cg too far back when inverted?

mauryr

I don't doubt the canards would be effective at high speed, but I don't think I would need any more throw for high speed flying, and canards would just add drag, weight and one more failure point, other than costing me 2 more servos.
About landing slowly: I haven't tried with a turbine installed yet, but as you can see in the first video I posted (maiden flight) the plane slows down extremely well as it is and likes high alpha (I actually touched the wingtips on touchdown, and I didnt even have to brake).

erbroens

This also happened to me in 1999, but with my Kangaroo.. the funny part is that while the plane was falling (seemed hours) I heard people saying "Look, Enrique visited the USA and learned to do 3D with jets!!!" LOL

I also landed inverted, and luckily I didn´t chopped throttle when it was low.. otherwise it may have pointed the nose down and crashed much harder. This plane is flying up to this days!

mauryr

Ahah, I received similar comments...
Mine has also taken very minor damage (one snapped fin, crushed airbrake area and shattered canopy), which was easily repaired. Luckily, since it's EDF powered, I managed to chop the throttle to idle right before touchdown, avoiding fod damage to the fan.

Yaw 7211

Here's from Hobbytech Malaysia, with a P80.

Mint condition and still in service, flies great!

Fantastic jet, simply love the air brakes.

1ricardo

My Feedback: (25)

Hi All,

Hey Jessus since you are building a new one, here´s another thing that i used to build on my Hot spots.
I install a tab on the back of the airplane with arroud 30 degress, basicaly a straight line between the turbine case and the end of the fuselage at the root
What it does is allow me to take out the ALWAYS trim up on the stab, wiche´s a lot and with that the stab trim is flush with the wing, and once the trim is 0 the servo don´t need to hold the trim position during all flight and it save a lot of the battery and servo, also it allow the model to fly at a much lower speed once the aileron is zero ( wiche is good) instead of positive trim ( wiche is bad, once it change the airfoil shape) and reduce a lot the tip stalling a high alpha and i thing the airplane fly i little bit faster.
You may try, here´s some pics for you consideration

Thanks

Ricardo

BaldEagel

On the Rookie the instructions say that the elevons have to be 3mm up trim if I remember correctly, never had to trim in upright, just a small amount of down elevator needed in inverted flight.

Mike

mauryr

My hotspot requires a good 8mm of up trim to hold in level and reducing it would be very welcome. Wouldn't changing the thrust line cause issues with trimming when increasing / reducing power though?

erbroens

Excellent idea, thanks for sharing it!