Right, and if that was the only consideration, airplanes could be designed by bridge architects. It's not that simple.

Seriously, I've pointed out the problems I've seen, but I don't think the builder is a bad guy or stupid or anything. In fact, it's appreciated that a Brit chose to spend so much time & $$ modelling a classic American bomber. I just think at that level, multiple failures indicate that requirements need to be a step higher than they are. That includes design choices and flying choices. Obviosly, the way it is, hasn't been working for this model, and the danger is real.

Johng,


Your last post is faultless as far as I am concerned (well the bit about a classis American Bomber may be a bit rash......) but seriously, lessons are around.

Those should be learnt, analysed and then, if feasible, no reason why another project could not commence.

If unreasonable, then that thinking is published and made good for the rest of the world to profit from, after all, that is the courage to fail, and Gordon has done that, big time!!!

Gazzer

And the way you show that has been accomplished is to do a true redesign and a full technical report that substantiated the critical strengths of the aircraft and the reasons for the design approach. As a redesigned aircraft, it should come out considerably less weight, and hopefully, with maybe 4 engines instead of 8. A 3m sailplane wing can be built to withstand 200+ lbs of lift with structure weight of less than a pound. A project like this should have a similar level of structural efficiency.

Bring a full report to the LMA that shows a good deal of structural improvement (lighter) and more simplicity (less engines) and maybe the LMA reconsiders.

The Phoenix rises!. On display at the LMA meeting, w/e March 6th 2005---another B52 by Gordon Nicholls.

Also a 13 .5 foot wingspan Airbus 320 with 2 x TJT turbines. Weight 100 lbs. A 1/3rd scale Hawker Hunter at nearly 12 ft wingspan..Should be an interesting show year. Pictures in June RCM&E and Aviation Modeller International for May.

You must mean his second B52 which crashed recently due to structural failure, battery moving, whatever.

Not a third B52, surely ?

You could be right, although have not heard of a recent crash. Still leaves the others to watch!

Plenty of bigun's out there,

I believe an Airbus 380 is on the cards from the redoubtable Peter Michel from Germany. Huge, to say the least. No objections appear to be raised to this one?

I don't know what procedures are in place around inspection, engineering and design.

Presumably everyone would apply the same kind of rules to all of the fabricators and fliers.........

Like I said, lessons could be learnt for the benefit of all.........

Gazzer

Yup - there's some info about it in the latest copy of RCJI

Gordon

Nothing better then marmite on warm bread.

I would like to hear Wren turbines view on this matter.

Oh and Wren do you like my pic of your 66mm wheel?

That is a work of art photography wise.........

I should imagine Wren are dissapointed, but I would also guess that they have achieved something pretty unique in 8 model jet turbines autostarting and operating..... quite a feat whichever way you look at it!

Gazzer

if the turbines aren't to much damaged, they can still sell then on ebay...

"used MW54 powering a B52..survived 2 crash.."

Or post them to me

Well guys, bottom line is this.

A really beautiful bird, that took more time and money than 99.9% of us would ever consider throwing at a project like this, turned into tooth pics one day. Pilot admitted error. The basic fact is that we have all been bitten by the GOTTA GO BUG, dang thing bites hard sometimes.

I would like to think of my self as a good pilot and have been told by many others that I fly well. I build very sound planes and fly them with quality hardware. There is no way on god's green earth I would have tried the sticks of a bird like that.

And after watching the video I would have to agree that the wind had a great deal to do with the crash. There have been several good explanations in these posts regarding stall speed and such when turning in the wind and it doesn't really fit to go over it again. Many R/C flyer's have lost their planes in a similar fashion and never realized that their air speed was not enough and their angle of bank was high enough to stall the wing. In fact I saw a full scale STINSON RELIANT almost go in while flying at our club field at the local airport. My friend and I watched him roll out and lift off. We both fly full scale and we both said it at the same time C$%P HE IS GOIN IN. It was an amazing thing to watch a plane try to fly and not be able to do it. I would bet the pilot didn't even know how close he was to going in as he did not lower the nose or reduce the angle of bank. As soon as he approached 90* to the wind the plane just started slipping out of the sky. Luckily he got around and started building airspeed before the wing stalled. It was close and he kept that nose up.

Anyway, it happens and we gotta remember the GO BUG. Sometimes it just takes all our common sense out of our heads.

I also have to wonder if maybe he had a turbine not coming up to full power??? The plane looked marginal for power. The problem with the video is that you do not get real and full effect of what is happening. The take off looked very scale, if you ever had seen a 52 take off, it looks like it going 10mph and will take forever to get up. I think if the fellow had more room and or less wind things may have been different.

Thank God he didn't pile it up in the crowd or and adjacent home.

Have fun, happy flying

Here is some video of a plane 12 foot long 12 foot wing span...
The thrust to weight was close 1:1 dry..

If your going to build a large plane, it needs to be light and powerfull
in order to make it as safe to fly as any other model airplane...

Also I don't understand why the second B52 was also very heavy.

http://www.corpcomp.com/weeks1/Movies/DC10.WMV

http://www.corpcomp.com/weeks1/Movies/DC10_2.WMV

Eddie Weeks

Gotta love DUCT TAPE. That was some sweet video and you can really tell that the DC 10 have a great thrust to weight ratio, especially adding a three pound handi cam to it and a half a roll of tape.

One thing for sure, the first landing on the second video was a bit iffy. I don't know about you guys but he was landing into a stiff head wind and I would have liked to see just a little more power. It is one thing to float our trainers in on a head wind but a high performance bird ??? Just my thoughts but a little more forward airspeen on that landing.

Gotta disagree, dave......check out full scale airliners, they are slow...coming in hot on these birds looks outa place. On the other hand, that flying was nowhere near scale anyway...

What part do you disagree with. I live right next to Grant Co. Int Airport and they fly every type of jet liner and cargo here 7 days a week as it is one of the best training facilities in the country. In fact Japan Airlines has their 747 training here.

If you watch the second video post and look at the first landing he is floating this plane in on a stout head wind and his forward airspeed is marginal. If something were to go a little wrong here he had no time to spool back up (jet lag and it doesn't refer to our bodies after a long flight) or enough speed to have great effectiveness for corrections. I am sure you know some who has floated in a sport plane and done damage to it because something went wrong on the flare.

How can you call 150 to 180knots slow? That is the average landing approach speed for many large jets.

Dave, accually the airliners have an approach speed of around 140 kias, with touchdown below. In fact, an empty 747-200 is stalled at 86 kias, leaving the approach at 115. Looking at the size, that is one slow bird hanging in the air. Scale that down to model size, and we are talking trainerlike landingspeeds to look good.
The approach to the second goaround in the video is looking scale when judging from ground speed, the one in the first video is definetly way too hot.
Now i do agree that this type of approach is not the easiest to fly nor the safest for the model when something goes wrong, but somewhere inside of me there is this strive to look as real as possible when i take one of my birds up. As for turbine spoolup: i put flaps, speedbrakes and anything i can think of that causes drag out on approach, allowing a higher power setting. When something goes wrong, i flick all of that inside and can go around without even having to add much power. Mean trick, but works....
Another thing to consider is the immense overpower...he does not have to reach full power to go around...the "neccessary" rpm is probably reached in a jiffy, leaving the rest of the spoolup for safety.
You are right, hot approaches are the safest, but to be honest: they don't look good, and at least for me thats not what this is about
Regards
Hank

Ok Hank. You give some examples of air speed indicated which is not air speed true and also does not represent an accurate stall speed. The plane in question, unlike the full scale bird it represents, does not have all the devices to control flight that a DC 10 has and there fore can not be flown with the same assumptions as the real plane. Also some of the speeds you show are empty weights.

I an not trying to get in a pissing match but infact just wanted to point out the visual apearance of the plane landing and that it appears to be near the edge of control if something were to happen. I think even 3 mph more would put the plane in a safer speen range. A typical turbine needs seconds to spool up and on that approach the pilot did not have seconds to try a powered up go around.

And yes, on the first video he came in hot and his flare was not the greatest and you can really see that the oleo struts really proved their quality absorbing the landing.

Of course if you had the full scale plane with all the stuff hanging out you would obviously have to have power in to maintain control and if you had to go around you would have procedures to do so.

Bottom line we have seen and or even crashed a plane on final approace bcause we were to slow trying to float it in.

Because they used incorrect materials and insufficent engineering.
I admire the project, but you seem to be the only person who points out the MAJOR flaw, overriding flaw, on both of these beasts...massively overweight, and underengineered, and an accident waiting to happen...whatever form that accident took.
Two different forms so far.
The fact that the second one came out a HUNDRED pounds lighter, what does that say?

It say clearly that hindsight is a wonderful thing and I personally use it in everything I design and fly....... which is why I have never designed and flown something by me

Lessons to be learned from the courage of others to fail.

Better go and start learning CAD....

Gazzer

The second was a HUNDRED pounds lighter???? HOLY CRAP!!!! I did not know that. Maybe the third will have negative weight!

Hi everyone,
I've been following this thread and it's really strange how some people think.
When the B-52 was first shown, it was the "wow" factor, everyone thought it was great achievement.
Then it crashed and almost everyone, at least here in the US, started criticizing Gordon: it was too heavy, not engineered right,
didn't have any composite's in the structure, too complicated, too big, and on and on.
An amazing turn around, wonder if the reaction would be the same if it was still flying.
Give Gordon credit, he had a dream, he got the resources together, engines, radio's etc, to make the dream come true. He built the BUFF, flew it around 50 times before it went in. And just to refresh everyone's memory, it went in because of pilot error, not because it was structurally and/or system deficient, so he must have done SOMETHING right when he designed and built it!
If it wern't for dreamers like Gordon and people who want to push the envelope, we'd still be flying single channel tone w/vacuum tubes.
BRG,
Jon

That's not true AT ALL.
When news of that model first came out, a LOT of people worried that it was just too much. Myself included.
I don't think the model really teaches us much...it's just a very large balsa model, not innovative, just LARGE.
Just making something BIGGER does not make it "innovative"...it could be just BIGGER.
I take that back...it DID teach us something...that balsa and ply and conventional modelling techniques are probably not adequate for a model of this size and weight.

I think Eddie Weeks' model was innovative. He applied some thought and engineering and ended up with a DC10(two of them) that were light, safe, and incredibly STRONG.
I know the first crash was pilot error. The second, nobody knows. But a third was inevitable, if they let him build a third...which they won't...which says something.

The model is very cool, and you have to admire the builder, but my feelings are he pretty much found out the upper limit on size, weight, and complexity, and I really don't see a need for others to try to outdo him. But somebody will try, I'm sure.
I just think when you get into 300 pounds, it's insane to be thinking just scaled up balsa and ply model airplane construction, I think you need to be thinking of actual engineering skills, math, computer modelling, stress testing, fatigue cycling, that kind of thing. Because 300 pounds and eight turbines and several gallons of fuel...man, that's a whole nother story.