|Jul 09, 2014, 10:44 AM|
Joined Mar 2012
I’ve been following this thread with great interest as I am like Stephen73 in that I prefer scale models. I too am looking into getting into turbines. The advice I received from the 2 jet flyins I’ve attended suggest the same approach as has been mentioned here, basically start with a twin boom bird. Still, I can’t get “scale” out of my head. While I haven’t made a purchase yet, in the end I think I will go for my desires. I guess this makes me hardheaded but oh well.
I’ve examined what available and here’s my thoughts:
A single engine
Wide track LG
Moderate slow speed capabilities
No to limited tip stall tendencies
Reasonable cost (for scale jet)
I’ve considered the following:
F-15 – One of my favorites, meets all requirements but the narrow LG
F-18 – I seems all F-18s are forgiving, ( at least the EDFs I’ve flown), has that nice trailing link main gear for grass fields but again, the narrow LG is a problem.
SU-27/SU-35 – This is a pipe dream for me, only if things work out. Hey, don’t laugh, I NEVER thought I’d be at the level I am now when I started.
F-20 – This seems to fit the bill for me. Doesn’t look like it should but don’t let the small wings fool you. Check out the video. No knee action LG but you can’t have everything. Besides, no one makes a decent F-20 for EDF. This too is a favorite of mine.
Not that I’m bragging but I have been successful with all my aircraft (Warbirds, twins, Scale EDFs, etc) over the last 34 years. My very first plane was a pattern/sport plane… flew that arf until it literally wore out. I still remember stripping the gear out and putting it the trash.. It died a very graceful death.
and this one:
|Jul 09, 2014, 10:59 AM|
Joined Nov 2002
My first jet was an F-86, which is still flying 10 years and 600 flights later, so my feeling is that a jet "trainer" is not a requirement for success in jets.
I have always said that my opinion is that the jet "trainers" are not trainers, they are sports models with jet engines that teach you little good and potentially lots that is bad for scale models. In the same way that being able to wring out a Wot 4/ Ugly Stik type of model teaches you nothing about flying a highly loaded warbird, and actually gives you bad habits because they teach you to get into situations with impunity, which the warbird/jet is not going to recover from.
If you want a twin boom, get a Vampire and at least have a scale twin boom!
My opinion is go scale straight away but be very careful which model and from which manufacturer, many innocent looking scale jet models have tripped up the most experienced pilots. John Wright and others have given very good advice earlier in this thread.
|Jul 10, 2014, 01:07 PM|
United Kingdom, Bishop's Cleeve
Joined Feb 2013
Was good to chat to you at the club BBQ a few weeks back.
I've bought a house since then but am working towards getting a scale jet. I'll need to consider what model is best.
Currently I'm looking at the Philip Avonds F15, a vampire / venom of some sort or a Mig15 with trailing link oleos, or a Peter Adolff U2. The U2 should avoid the issue of a sudden high sink rate on approach whilst still learning throttle management.
|Jul 17, 2014, 02:22 PM|
Joined Mar 2010
To Stephen73 - IMO, you've gotten good advice from Gunradd, Invertmast, and HarryC.
And youtube is your friend: plenty of videos out there showing how the various jets handle and land, so you can judge for yourself. Pay particular attention to landing technique and the F-16 and F-15 in scale jets. You will notice that the F-15 in particular will be the easiest of the scale turbines to land, as long as you do a lighter build. The ARFs and kits for these have been out a long time and most of the bugs have been worked out. And the models from Skymaster / GJC/ JL and Avonds have many design tricks in them, including lots of washout, that make slow-speed handling superb. You will also see lots of turbine pilots who fly a great routine and then do a poor landing where they are trying to chop the power and use the elevator to control altitude. Everyone needs landing practice all the time!
That said, all turbines will be heavy: the airframes are built heavy, and there is a lot of fuel to carry. Everything is "overbuilt" and overspecced. A typical 1/9.5-10 F-15 with adequate power (100-120N)will be 32+lb wet on the ramp, consisting of 20-22lb airframe (retracts, fuel system, flight batteries, fuse, servos), 3.5lb of engine and ancillaries, and 6-7lb of fuel.
With the typical 7ft sq ft of wing area in this size model, you will be at 70oz/ sqft at takeoff and 60-ish at landing. The turbine will consume between 4oz at idle and 12-16oz at full throttle (up to 1 lb/min). You can expect to burn 4lb of fuel per flight between taxi and flying. 60oz wing loading sounds huge, but you have to remember that lifting efficiency of a wing increases at 50% of the area increase, so a 32lb 1/10 scale F-15 with flaps will land with the same degree of difficulty as a 26oz wing-loaded .25 sized plane (imagine a 4lb GP Super Sportster). Of course, the cost of a mistake is many times larger in the jet!!
And there is really no way around the weight: you may be tempted to put the smallest recommended turbine in and carry as little fuel as possible (that was my thinking at first) but you just trade one set of problems for another. Without reserve power, you will watch your model eat up a TON of runway on the rollout and struggling to get into the air, and you will white-knuckle it down because you have no reserve power or fuel. Like the warbird guys, most of the experienced jet pilots don;t worry a whole lot about wing loading. They just follow the recommended setup.
IMO, experience with flying and landing heavy metal warbirds is a pre-requisite to turbines. Practicing on a heavier EDF setup (again in the 26oz/sf WL range) will be useful as well in terms of learning the approach, managing the sink rate with elevator and throttle control, and flare. You just have to keep in mind that you can't just jam on the power with a turbine they way you can with an EDF: if your sink rate is faster than expected and you are behind the throttle, the turbine will not forgive.
I'm new to turbines myself and, not surprisingly, my first turbine is a Jetlegend / GJC F-15, and it is a great first jet. Looks great, sounds great, very stable flight, and not hard to land provided you keep a few things in mind. The key to success IMO is not just plane selection, but finding a good CD locally who will take the time to teach you all aspects of turbine flying including (most importantly) safety, and completing the Turbine Waiver process. This should include lots of time on the buddy box with your CD, so that you are proficient with that airplane and know it inside and out, warts and all, by the time you are Waivered.
|Category||Thread||Thread Starter||Forum||Replies||Last Post|
|Found||Looking for Spektrum DSM2 Aircraft Module for my Futaba 9c||airbagit13||Aircraft - General - Radio Equipment (FS/W)||6||Apr 03, 2014 12:23 PM|
|Question||Looking for Plans for Scale Model Warf||hookpilot||Scale Boats||5||Nov 17, 2013 06:30 AM|
|Found||looking for two SPMSA6260 HV digital hi-torque mg aircraft standar||jenna||Aircraft - General - Radio Equipment (FS/W)||0||Sep 25, 2013 07:22 AM|
|Discussion||Very Rare Aircraft, Heston A.2/45, Looks like a nice design for Electric Scale.||Jimmy James||Scale Kit/Scratch Built||5||Sep 17, 2006 08:33 PM|
|Looking for my first jet||captnklutz||Electric Ducted Fan Jet Talk||12||Sep 08, 2002 01:16 PM|