Large Model Association Forum

I will be building large scale model of famous B-52 Bomber. I know there have been guys who have already built fairly large models in past and from my understanding being 8 turbine powered BUFF by Gordon Nickles. I would like to know what areas do i need to concentrate most on the wings and fuselage. My model will be powered by 8 EDF units. I'm not sure if i will have retractable landing gears fixed gears in order to save the overall weight of the model. Scale of my model will be 1/10th or 1/11th corresponding to around 16 feet +- wing span!.

My other question is about wing flex, dose a model of this size needs it as how real aircrafts have or should it not be good to have if risk of failure is greater?.





Ps. I would like to get in touch either with Gordon or Chris Golds if someone on here could connect me to them, Thanks

Cheers,
Sam

B52 - an delicate subject in the LMA. There are a number of these currently being built in the States with various power trains. Having designed large EDF models, the latest being the Concorde, may I suggest you carry out some basic design calculations first. With a wing span of 16ft the model will have a wing area of over 20 sq ft, a design loading of say 32ozs/sq ft would give an AUW of around 40lbs. The power required to fly such a model with authority would be approx 5000 watts min. In order to obtain the eflux velocity from the fans I would suggest 1kW fans as min requirement. In order to obtain the fan speeds the battery voltage needs to be high at least 8S lipo drawing 40A. With 4 EDF on each wing there is also a need to balance the weight/power distribution and spar construction for assymetrical flight as the rudder on the B52 will not pick up a wing drop past approx 20degs. Taking all these factors into account the weight of the power train and its components will be in excess of 32lbs which means that the model AUW is likely to exceed the 20kg limit. I would therefore suggest that you contact Tony Hooper who looks after the over 20kg scheme and have a chat on the project which will answer most of your queries.

here we go again!

I think Paul is refering to the recent postings about the fanciful 1/4 scale Vulcan- This is a bit more realistic, but someone with the knowledge of flying a prototype with the almost unflyable characteristics of the B-52 should come on here and impart some sense! The construction of a model B-52 would certainly have to take account of the enormous stresses imparted on the wings by 8 (or even 4) motors powerful enough to lift the beast. Personally, I dont believe it can be done safely with the materials available today.

IVAN GOODCHILD wrote:B52 - an delicate subject in the LMA. There are a number of these currently being built in the States with various power trains. Having designed large EDF models, the latest being the Concorde, may I suggest you carry out some basic design calculations first. With a wing span of 16ft the model will have a wing area of over 20 sq ft, a design loading of say 32ozs/sq ft would give an AUW of around 40lbs. The power required to fly such a model with authority would be approx 5000 watts min. In order to obtain the eflux velocity from the fans I would suggest 1kW fans as min requirement. In order to obtain the fan speeds the battery voltage needs to be high at least 8S lipo drawing 40A. With 4 EDF on each wing there is also a need to balance the weight/power distribution and spar construction for assymetrical flight as the rudder on the B52 will not pick up a wing drop past approx 20degs. Taking all these factors into account the weight of the power train and its components will be in excess of 32lbs which means that the model AUW is likely to exceed the 20kg limit. I would therefore suggest that you contact Tony Hooper who looks after the over 20kg scheme and have a chat on the project which will answer most of your queries.

Ivan,

Thanks for chiming in, since you have mentioned that there are number of other large B52s that are being built in US presently, could you please link them on here. I would like to see how those guys are building there models. Presently my main concern is construction of the wings for this model, since fuselage is already built by another modeler rest is up to me to build it and fly it.

I also would like to know what type of spars are being used and are guys making foam wings or built up wings. I am also concerned about wing flex if that is needed on the model or not and if it's needed then how guys are achieving this critical aspect of there builds. I will be looking at EDF units and how many to use once i can get airframe weight established of this model other wise it's waste of time to look into them at this time.

Does anyone on here have more good close up pictures of RB-52E CCV 56-0632 (cn 17315) vehicle as ^^?
This was very different and unique bad boy then any other B-52s ever built!. It used a lot bright red on fin, forward fuselage, leading edges of wing outer fuel tanks and nacelles!, plus it had 2 small canards on forwards fuselage, 1 ventral small fin and very long pitot tube on the nose of the aircraft.

I want to replicate my B-52 after this bad boy, i would appreciate if anyone on here could provide me with it's close up pictures, i don't A.net's link as i have whats on there but i want from other angles. Thanks

Anyone know where retracts for these B-52s could be readily bought from or custom built from?