OZZ

The yellow aircraft supply a blackbird sr-71 I'm trying to research this aircraft as a future model has anyone recently flown or built one. Any info would be grateful please. One question why is it only ducted fan and why not a turbine??. As I said any info would be appreciatted.

Duncan

Shaun Evans

Ozz,

I think the reason you don't see them with T-power is that the airplane is very tricky to fly. I'm not bashing anyone's product (hey, wait a minute....), but a fact is a fact. You don't see too many of those airplanes around because they seem to have a very narrow 'safe-flight' envelope. I suppose nobody wants to jeapordize two turbines in such an airframe. Hope this helps.

Doug Cronkhite

My Feedback: (34)

The problems with the Sr-71 flight behaviour would be easily tamed by a gyro on pitch control.

John Casey

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Its also a couple of inches short in fuse length,
it should have been 107"L with a 55" ws not 105"L with a 55" ws

grbaker

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after seeing Dennis Crooks fly his at the SW Fan Fly (Remember when they were called fan flys) So he called Dennis to find out how it flies. Dennis stated that one of the big problems with the SR71 was that it was extremely difficult to fly on one motor. I believe I read somewhere that a flameout on one side of the real one could put the pilot's head into the canopy so hard it would damage the helmet or canopy or both.

One other factor he mentioned was that you need a full size runway to fly it from. It actually gets off the ground in under 600 feet, but he felt it would be impossible to land in less than about 1000 feet. With the residual thrust of twin turbines, I'm sure this distance would be much greater.

My friend decided not to buy one.

I have video that I took of Dennis's flights of the F-14 and the SR-71, and they were awesome. I hope Dennis gets back into jets someday!

Brucem

G'day All,

I have a D/F Blackbird and will be test flying it in the near future.
Had a few problems with fuel but have sorted the out now. I will need a large runway more so for landing.
I have been flying a smaller rocket powered blackbird and have learnt alot with cg setting and getting use to the shape in the air.

Regards
Bruce

LGM Graphix

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I've dreamed about doing this jet with twin RAM750's, but I've wondered why you never see many so haven't really considered it seriously, but man I love the jet, I'd love to build and fly one.

steve ho

brucem,

i just wondering is ur sr71 a yellow aircraft or a ross hobby plan version???

as at the mo i got hold of a set of ross hobby plans, so i would be keen to learn the flying characteristic of the plane.

plus if lengthing the wing span would it help to stabilize the plane even more??

regards
steve

OZZ

Spoke to Yellow Aircraft
They said that it was an old model, they had heard of a flyer with twin t's but the besides just going around nothing else could be done with the aircraft. Still A nice bird to put into anyone collection

Brucem

G'day Steve,

Mine is a Yellow Aircraft, It has been sitting around for a while but should make it into the air in the near future. Just have to finish my current project.


Regards
Bruce

steve ho

hi ,

have anyone heard of anybody getting a ross hobby sr71 up in the air?


steve

John Casey

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I have a completely built Ralph Salvidar (Knights of the Air), scratch built SR-71, Anybody put one of these up ?

Capt. Crash

My Feedback: (1)

OZZ,

I'm happy to say that your question of an SR-71 with turbines has been answered. My friend Dennis Crooks has done just that this year in 06. He put in (2) funsonic 12lb thrust engines in a Yellow Aircraft SR-71 this year. I seen him fly it at Windy City Jets this year. Outside of having a little brake drag problem, the jet flew really well & fairly FAST. I would guess in the range of 150-170 mph. I would say that was good for 12 pounders. The SR we are working on is a Ralph Salvidar all wood scratch built with 28lb PST turbines. A little big for the 1/12th scale, but I plan to use the engines in other jets after the SR has done a few shows. "I Hope"...
Yellow Aircraft no longer makes these kits. In fact, they cut the molds up per the guy at Yellow. I was looking for struts for my SR & that was the information I was given because I was asking about buying a Yellow kit to build as well. We hope to have ours in Toledo in 07. We have lots of detail going into the jet & should look fairly good on static display.
As someone else has mentioned the SR is a NOT SO FRIENDLY aircraft to fly per Dennis Crooks. He makes it look easy after all these years, but he will tell you even after as many flights as he's had on the SR-71, "It demands ALL of your attention while in the air".
Take Care

Capt. Crash.

Mike Emilio

I studied the original Saldivar drawings and compared them to the Ross drawings. The Ross drawings appear to be a trace of the original Saldivar. This aircraft was originally designed for D/F. So , , , armed with the two drawings I totally re-drew them but this time in AutoCad. I was surprised to realize how many parts had minor errors, and alot were not symetrical. The new drawing is now for a larger SR-71 that will hold suffucient fuel for turbines. Span is 73" & length is 138".

ECalderon

Hi guys,

For those of you who like the blackbird, take a look at this web page.


http://www.mmrca.org/lance/sledframe.html


Regards
Eduardo

Bob_B

My Feedback: (11)

I saw Dennis Crooks fly a new SR-71 at Windy City Jets with Funsonic Turbines. He only flew circuits with an occasional roll in front of himself. Very difficult to see in the air!

Dennis Crooks

As long as the set-up is proper, there is no reason to be afraid of the Blackbird. As BRUCEM mentioned, it can be difficult to maintain orientation. An advantage to the turbine version is that it is a little faster than the D/F so for the first few flights you can keep it in a constant shallow bank on the downwind side of the traffic pattern. This way, there is no confusion as to which way it is turning. As you develop more confidence in the model and the engines, the SR is entirely capable of mild aerobatics, slow roll, 4 pt. loop, etc. No gyros, not really needed.

Runway length for the first few flights should be as long as possible. Not so much for t/o but for landing. If the SR slows down too much on approach, it can wind up landing on its tail. The D/F version was radar'd at 52 mph for t/o and for landing. I suspect the turbine version is a little faster. A friend of mine made up a set of scale wheels and brakes for all six mains. Stopping is not a problem.

FWIW a 1/2 pound coffee can holds 64 oz. and fits nicely in the fuselage area for a fuel tank, 2 of course.

Lance Campbell

I ended up with 3 years / 16 flights on my Y/A Blackbird, before retiring it, and eventually selling it. Like Dennis has said, with a solid power supply, it's not that bad to fly. The first 3 flights all had engine failures, then after engineering 3 separate fuel systems for it, got reliable runs and finally got it sorted out. It was the confidence in turbine power that pushed me over the edge to build the one I'm building now.

At the time, the AMT Mercury, was about the smallest engine you could get, and I felt 2 18+ pounders would have pushed the wing loading too high on the Yellow SR, and would have been over kill. The choice of a couple smaller, 12 pound engines for a Yellow sized bird would seem about perfect to me. But I'm way too far down the path to redo to a smaller size. That was my original thinking in scaling up 50% to the 1/8 size I'm building on, based on 2 18 lb engines. Now with rules changes, I'm going to see if I can get 2, 25 lbs in it and make weight, but I'll have to see on that one.

I've helped a few others on theirs too, and can confirm the stall is nasty. Literally, nose pointing straight up, stopped flying type of stuff. Pulling it into a nice pretty deep stall on landing is a living dangerous, until you know where the line is.

Molds should be finished by this year, and prototype being worked on this winter.

Anyhow, Grats Dennis on your bird, and good luck to anyone else giving this critter a try.

Eduardo put the link above to the build page, for anyone wanting to follow along.

Lance

Mike Emilio

Lance . . .
Your project is simply mind blowing!
My Saldivar/Ross redraw of the SR-71 kept me buisy for quite a while. I incorporated your ideas on how to make that crazy drooping leading edge. I'll probably start templating next month. When will you have another photo update on your site?

My appologies OZZ, don't mean to hijack your thread, but Lance is definitley my hero and couldn't resist!

Lance Campbell

Quote: "When will you have another photo update on your site? "

It will be probably a couple months yet. I mentioned on the last update some personal things going on, that were going to grind work on the Sled to a standstill for 6-8 weeks or so, and that time has now passed.

I'm getting back to work in the basement now, and have spent the last few evenings cutting balsa trees into little cubes again, in preparation of the bottom mold layup. The top mold and fuse plug are back in the paint room, jigged up, and about half the fence that is needed is in place.

This may sound crazy, but I'm excited that after 4 years, this winter I may actually get to start making parts of an airplane that might fly!

Lance

juninhodunai

in where I see the video of this SR71?

kevinlmoses

Where can I find Ross Hobby plans?

tomcatman

My Feedback: (2)

Is it just me? I keep getting a "Forbidden" error message when I try to access Lance's SR-71 website.

"Forbidden
You don't have permission to access /lance/sledframe.html on this server.

Additionally, a 403 Forbidden error was encountered while trying to use an ErrorDocument to handle the request.


--------------------------------------------------------------------------------

Apache/2.2.0 (Linux/SUSE) Server at www.mmrca.org Port 80"

kevinlmoses

Yes. I got one of those, too.

tomcatman

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The site must be down temporarily (hopefully, just temporarily!). Thanks,

Richie