tp777fo

My Feedback: (28)

I'm having a blast with mine. Jet Central Rabbit for power. The smoothest landing jet I have ever flown.

Beachy1968

Just got back from a great weekend away at Wings and Wheels with my 9 year old boy. Despite all the fuss made by old DB Sound about a certain Horizon Hobby employee I personally thought that the most impressive flying of the day today was Dave W demonstrating the Xcalibur. I just love the way he does those snaps and tumbles. Off to bed now that I've unpacked the new toy I bought back from the show!

Dave Wilshere

Mark

Wouldn't say the flights this weekend were that great, each time I landed with half a tank (second part of the flight is more fun as its 2lb lighter!) yesterday the strong cross wind bounced it around and the the landing was pants!
Scheme looks great, I took this shot of Colin's RAF scheme, pity his turbine troubles stopped us flying together.

Dave Wilshere

Another Video from the weekend at the WIngs & Wheels show. Tight airspace and gusty conditions perfect for the Xcalibur. Short flight only, I landed with almost half a tank!

<iframe width="640" height="390" src="//www.youtube.com/embed/1Wx2pmtXUR8" frameborder="0" allowfullscreen></iframe>

jetster81

Well demo'd Dave, just goes to show it is strong as well as nimble.

Dave Wilshere

Had a few comments on the snaps, its holding up fine, though I did hit it a bit hard a couple of times. I don't fly it fast, so things don't generate.

D

76Mustang76

Have a few flights now under my belt now and i must say i just love flying my Xcalibur. Great Jet trainer/Sports model.

You tube video showing it in action.
https://www.youtube.com/watch?v=sxbA...PTA7mP7Cr9_A0Q

Dave Wilshere

J

Looking good,try wrapping the springs and legs with insulation tape (see my next RCJi article) Also can't see your flap angle, but you should be able to slow the landings down a little more

D

avionics

My Feedback: (3)

Daniel Did you manage to put P-100 in yours?. I have a BF Turbine 100 on mine but at idle the plane has too much thrust and have to the shut the turbine to land. Do you have any issue at idle with yours ??

Regards

Reza

Dave Wilshere

Reza

Think you mean me? Yes I have a P-100Rx is mine (many videos above) It does not creep with a JetCat
P-100Rx, maybe a lower idle thrust that other 100N turbines

Regards

Dave

Dave Wilshere

You can see at the start of this video the aeroplane does not creep!

Dave

<iframe width="640" height="390" src="//www.youtube.com/embed/BXFr8GsOnDg" frameborder="0" allowfullscreen></iframe>

avionics

My Feedback: (3)

Hi Dave my apologies for my mistake I misread the message it should have been addressed to you. I have a BF-100 in mine that the idle is set to minimum it can be at 38000 RPM and the plane creeps very fast on the ground. I contacted Christian and he recons that 38000 is the optimum idle and below that gives me problem. I always used jet cat in my planes and NEVER had an issue with any of them this is the first time I am stepping out of my box and have not a good experience with it. Can i ask you what idle RPM is your 100RX ?

Regards

Reza

Dave Wilshere

Reza

No problem, I answer to most names :-)
The JetCat is 40,000, but that does not tell the whole story. I see on many turbines a higher idle thrust than JetCat...that's the difference I see on development, its possible to push these turbines to big thrust levels, but you don't get something for nothing!

If you reduce the idle further reliability will be compromised

For landing all you can do is add drag (split rudders, CROW and full flap) On the ground try increasing the friction on the nose wheel by adding tygon tube over the axle (between the Fork and wheel bearing)

Dave

avionics

My Feedback: (3)

yes dave you are correct I was thinking on the same line to add frictions on the ground and in flight. Thanks for your help and regards.

Reza

76Mustang76

Hi Dave.
Video was taken on my forth flight and landing was a bit fast. Since then I have made some adjustments. Increased flap to about 80mm which seems to have helped. Still to programme in some crow once I figure it out on transmitter. Whats the reason for the insulation tape on springs?. Does it make them a bit stiffer and less bouncy?

Jeremy

Dave Wilshere

Ok
More for dampning, like when you turn around on take off and one side dips

Beachy1968

So, I finally managed to start my Xcalibur properly today. For a couple of reasons I will be installing things a little differently to the way most people have done on here. Firstly, I want to leave the option open to have a play with a smoke system so I will be putting the air tanks up front to leave space above the fuel tank for a smoke tank. Secondly, I am temporarily limited to one turbine (Merlin 100XBL) which is currently fitted in my JL Viper and I want to install things in such a way as to make it easy and quick to swap this engine between the Viper and the Xcalibur.
Today I've fitted the control surface horns (call me paranoid but I went for Hysol as well as the screws!), installed the landing gear (thanks for the tip, Dave, regarding tapping holes for M4 cap screws) and then spent the rest of the day attacking plywood with a scroll saw!
First ply-bashing job was to fit baffles either side of the nose wheel cavity to keep the air tanks away from the nose wheel steering cables. Then I tacked the equipment trays. To make the Merlin easily swappable I want to mount the ECU, pump and system analyser on a small quick release tray which will sit above the steering servo. To do this I've had to make up new side trays which will sit approx. 15mm higher than the supplied trays in order to allow the fuel tank fittings to sit underneath the removable ECU/pump tray. The shape of the fuselage means that although the side trays meet in the centre I've still had to make two separate trays as a one piece tray is very tricky to get in. Pics of the trays installed to follow tomorrow.The final thing I've made up is a retaining beam for the front of the fuel tank. If I go for smoke the extra tank will sit on top of the fuel tank and so I think something more secure than velcro will be needed to secure both tanks as when both are full that's quite a lot of mass. It will also give me a handy place to mount the air tank filler valve.

lawndartz

SO is anyone else working on a Xcalibur ? I jsut got my radio & goodies for mine. Hopefully my Xcalibur will be here this weekend.

Dave Wilshere

There are plenty being built in the UK, just not RCU posters! The last batch sold out as it landed and the next batch is sold out while still at sea! Its a huge success.
Mark, looking good.

Dw

Beachy1968

Yes, I'm sure lots are out there being built but not everyone wants to make it a public event!

I personally like to post in detail about my jet builds because, although I've been a modeller of one form or another most of my life, I am relatively inexperienced at the specifics of building jets. Although I draw upon my past modelling experience, aeronautical engineering background and common sense, I like to show the more experienced jet flyers out there what I have done just in case I make a poor decision which could lead to problems. It hasn't happened yet, but much better safe than sorry... Since starting to fly jets I've benefitted a lot from those who are willing to share their knowledge whether on the internet, in magazines or just via a chat, so in the unlikely event that any of my posts give a little bit of that back then that's an added bonus.

Ricko1

Hey Beachy,

Keep posting ! I like some of your ideas.

I have just started putting mine together and this thread has been a great help. I've got a few ideas I will throw out there for comment - so everybody feel free to give me your opinion. As this is my first turbine ( and also my sons and his mates ) I am considering making it as light as possible. Engine of choice will be a Kingtech K60. I measured the stock fuel tank and it's just over 3 liters so I'm considering chopping it down to 2 liters - by Kingtech's manual that gives me roughly 10 mins at WOT. I'm knackered after 6 mins so that should be plenty of juice. So between the smaller turbine and a liter less of fuel I reckon it will be about 1500 grams lighter than most of the 100 powered Xcaliburs. I will be mainly flying off a grass strip so the lighter the plane the less stress on the gear. My mates who have jets all say I should get a bigger turbine so that later on a can drop it into a bigger model but I think I will be content with this one. I'll let my son buy the big one and I'll fly his. Like I said the more input I get from the experienced guys the better.

Cheers,

Rick

Dave Wilshere

The 60N turbines work fine, trouble is turbines are least efficient at full power and you need full power for longer times, so overall fuel use is higher.
Tank is 2.9 ltrs, with a P-60 I got 9 minutes as the early video of the silver one. My P-100Rx version does 10 minutes...same fuel.
Watch the later videos, take off and landing is very short. Weight is not an issue on the Xcalibur.
KT 60 is fine, but don't waste your time cutting tanks down.

Dave
Oh ignore turbine manufactures figures, KT 60 is 313ml/Min WOT So usable flight from 2ltrs is 5.5 mins

Grodus

Rick, if you dont already have the KT 60, why not consider a VT-80? On 2L of fuel, it will run nearly 2 min longer at WOT than the KT60 and produce 5-6 more lbs of thrust. You dont have to use that thrust if you dont need it but the VT-80 has a lot more applications with future airframes.
I think most of you flight with a 60N turbine is going at or near WOT. I fly mine with a Wren SS would only need 1/2 tank of fuel to fly 6 minutes, because im not in the gas all the time. The VT 80 uses less fuel than my SS so you wanted a light t/o weight and a 6 min flight, fuel to 1/2 a tank and have a very short takeoff and power to spare.

Dave Wilshere

http://www2.ripmax.net/Item.aspx?ItemID=A-JSM001/R

Detailed pictures of the RAF scheme

lawndartz

I love build threads, it helps those that are building. Helps with ideas & questions..