FlyFly Hawker Hunter

sihinch · February 03, 2013, 09:33:12 PM

I agree.

This model I would like to be a scale performer, with enough thrust and power for a good take off and climb-out.

The real Hunter, for it's time (1960's) was a quick aircraft, but certainly didn't have the power, climb authority and acceleration of the current generation of fighters. Although I gather it handled very nicely, especially at low level (around 50ft!)

With the retracts in, and fan and esc in place, plus servos, it actually feels quite heavy. I've not weighed it yet, but I think 73mph might be optimistic!

flying saucer · February 03, 2013, 10:51:02 PM

Quote from: sihinch on February 03, 2013, 08:53:32 PM
I agree that I am going for scale speed on this one, but it's about 1/9.5 scale (not 1/11.) It's 60" long! So 700mph will be about 73mph.

Sorry to correct you Michael.

Jeff - my power system considerations have all been listed previously, in this thread. All options have been determined as a result of research. The magazine article was 5S with stock fan and housing, which I know to be less efficient than the 3 fans that I am considering.

Sounds good Simon, I don't think you'll have any trouble meeting or

exceeding your target regardless of which setup you go with.

Michael · February 03, 2013, 10:52:25 PM

73mph is not really that fast.

A standard Parkzone Habu flies faster than that.

flying saucer · February 03, 2013, 11:00:53 PM

Quote from: Michael on February 03, 2013, 09:22:19 PM
I stand corrected, but my point is that some of us are flying too fast.

73mph is not that fast.

I am not sure I understand, too fast for what? Not everyone is a
half throttle or scale flyer. I like models with a very wide
performance envelope, and enjoy all types of flying. In addition to
full power flight, I often glide and do slow passes at just above
stall speed (by the way I don't think stall speed scales in quite
the same way as top speed).

Now if you look at many 3'rd 4'th and 5'th generation jet fighters
such as the F16, Mig 29, Su 27, Mirage III, F22 etc.. these all
have top speeds of Mach 1.7 to Mach 2+. Based on your calculations
an average 90mm model would need to attain around 130-150mph at
full power to fly scale.

As much as I'd love to have a 150mph EDF, In a lot of cases I don't think that's realistic. With all the
different types of models and power systems we can choose from,
there are just as many different flying styles each individual
modeller can enjoy.

If you wish to continue this discussion, perhaps one of the forum mods can create a new thread?

Michael · February 03, 2013, 11:13:21 PM

Too fast for scale; not necessarily too fast for fun.

However, most of our scale models are flown at faster than scale speeds.

I'm sure some of the models of modern jets are exceptions.

Ededge2002 · February 03, 2013, 11:39:40 PM

Off topic here but "scale speed" should not be calculated. It should look about right but not be a set number in my opinion. I would like to see a 40" scale Cub stay in the air for example.

Please note : all above is opinion!

piker · February 04, 2013, 12:03:58 PM

Flying fast is fun and we all take the opportunity to haul ass with our planes on occasion

But, if you're trying to recreate the essence of the full size, you need to fly much slower than you think. Yes, that can be boring compared to roaring by at full bore, but flying at slower speeds can bring a quality to the flight that makes the model appear and "feel" more realistic.

I'm most familiar with my own planes so I'll use them as examples. My Sandringham looks most realistic when flying by at just above stall speed. It's still probably flying much faster than "scale", but creates a much better effect compared to full speed. My Zero, that I was flying this past summer, was fun to blast by at full throttle, but appeared (and sounded) much more realistic when flown at lower speeds.

I know the tempation is to fly jets as fast as possible, because they ARE, after all, jets!, but to Michael and Simon's point, they actually look more realistic while flying a more scale speed. Also consider that when we see full scale jets flying in person, usually at airshow's, when they're low to the ground, they're flying well below the sound barrier, probably 500mph max. When you see an F-18 do a pass at the Toronto airshow, it takes several seconds to cross the view of the audience lined up along the waterfront. To recreate that impression with our model F-18s, etc., flying across Rogo field, we also need to take a few seconds for the pass in order to create the most impressive and scale like effect, especially with a "for the camaras" partial bank, for effect

BTW, I'm generally proud of us electric flyers as we generally do fly our models at a much more realistic speed compared to the glow guys. We know what the left stick is for. I HATE watching a glow model, say a cub, or a WWI biplane being flown around like an Extra. It's just damn ugly!

Robert

flying saucer · February 04, 2013, 08:10:59 PM

Well I guess everyone likes something different. When it comes to jets my personal view is that they are capable of flying as fast as humanly possible!

sihinch · February 04, 2013, 08:23:38 PM

Wings, anyone?

Wingnutz · February 04, 2013, 10:44:00 PM

I'll take mine battered with medium sauce and a side of fries.
Looking good Simon!
I take it you've decided not to do flaps?

sihinch · February 05, 2013, 08:30:16 AM

No flaps. I rea somewhere about this model not really needing them. But the real reason is that the aileron/retract servo wiring in to the fuse was already a pain, and I didn't want to add to it!

I added some carbon reinforcement to the fuse, over the wing shoulder last night. And then fitted the wing - I must have 3 to 4mm panel gaps! Looks terrible. So tonight I'm going to cut some blue foam fillers.

Wingnutz · February 05, 2013, 10:14:36 AM

Saw your post about ESC to battery lead length on Ed's power system thread. Are you going to try to re-locate the ESC closer to the battery?

sihinch · February 05, 2013, 10:45:26 AM

Yep! Gonna put the ESC in the cockpit, I think.

Stock ESC location is about 15 inches from the battery. And I've seen photos on RCGroups of the Hunter with an ESC fire, which after Ed's post I'm putting down to the capacitors letting go. So I'm moving the ESC!

Ededge2002 · February 05, 2013, 12:05:58 PM

Glad to help guys. Please also note the part about twisting the motor leads and keeping the ESC power leads tight together. I admit I have no first hand experience with this its just what research showed.

flying saucer · February 05, 2013, 12:45:53 PM

On one of my models, due to the design all the electronics had to be installed right near the tail of the plane. At the time I had vaguely heard from somewhere to keep the power wires short as possibe. Reluctantly I ran ridiculously long battery wires from the ESC to the cockpit where the battery went. Easily 30+ inches. Had 20 flights without a hitch. The ESC is now in another plane.

Please take this with a grain of salt as this is only my personal experience and do not want to over rule the experts.