Dave, why don't you post the project brief in full? That will give all the opportunity to better help you.

At 2kg weight limit, you might just be able to do a smallish ducted fan jet. Turbine? I suspect not....

hey thanks for the replies...yes i will be using a ducted fan not a turbine...
..the wingspan should be a MAX of 2m...thanks for the links provided..but i really want full balsa plans..which is very hard to find...can anyoe plz give me plans of that?

Originally Posted by AndyKunz

So the university must have some background experience here, if this is coming from above the prof. What have previous classes done? What school are you attending? Is this for the AIAA or SAE competitions?

Andy

I'm studying in the university of coventryy...and no this is not for any competitons..its just an individual project for my fianl semester of the degree.
Yes many people in the previous classes also had to do a project and i think all completed it somehow..we are actually allowed to make any plane..but i would prefer a fighter jet coz i had made previous fighter jets with my group in my previous semesters..

If you're making a unique design what would qualify it as a "fighter" ? I'm guessing you just mean something that looks like a fast jet. Unfortunately this is probably the most difficult possible aircraft to design from scratch or find a useful design to modify, particularly if it has to be made from traditional balsa construction. Almost all modern examples of such things (and there are hundreds) will be either foam or composite construction. E.g. you'll find lots of foam plans in the Foamies(Scratchbuilt) forum.

I wonder if part of the project's idea is to see which students are bright enough to choose a suitable type of model which will actually be practical to build and fly within the project constraints. If so I fear you may be failing at the first pass. Choosing the most difficult thing possible to design and build may not be the best idea.

Steve

If you are allowed EDF, maybe you can adapt one of these, as both are pretty qick and easy to build so you can do a couple of "prototypes" if required.

http://www.modelflying.co.uk/news/article/tornado/4805/

www.tonynijhuisdesigns.co.uk/MiG25-24.htm

Originally Posted by slipstick

If you're making a unique design what would qualify it as a "fighter" ? I'm guessing you just mean something that looks like a fast jet. Unfortunately this is probably the most difficult possible aircraft to design from scratch or find a useful design to modify, particularly if it has to be made from traditional balsa construction. Almost all modern examples of such things (and there are hundreds) will be either foam or composite construction. E.g. you'll find lots of foam plans in the Foamies(Scratchbuilt) forum.

I wonder if part of the project's idea is to see which students are bright enough to choose a suitable type of model which will actually be practical to build and fly within the project constraints. If so I fear you may be failing at the first pass. Choosing the most difficult thing possible to design and build may not be the best idea.

Steve

Hi steve..thks for your reply mate..i know there are lots of foam plans but unfortunately we HAVE to do balsa no choice there. See smester we also had to built a modified fighter jet..by modfied i mean he expects us to make our own plans and not copy it from some site...for example we made an F 8 and we changed some of the features..we put an additional landing gear and and we altered the tailplane.. etc..not too big of a modification just a slight one

That Nigel Hawes Tornado is looking better and better methinks.... will do well with a bit of tweaking to make it "unique". You may even be able to do a swing wing version.

Dang, I just ordered MYSELF a set of the plastic bits (and a Blenheim and a Sea Fury plan) and see I don't even need to do a project for Uni!

So long and ta-ta, I'm off to the shed to dig up the plan.... see ya all in a couple of weeks- and I don't give a damn if the damn 'roos are eating up the front lawn (again) in the meantime!

Odd

Well, structure is structure. It doesn't matter if the model you build is a glider or a "jet" fighter. So to start with studying any of the plans you can find on the web of any plane will give you some guidelines as to what sort of structures are applicable to achieve the sort of shapes you want. The plans do not NEED to be a jet fighter. If you can carefully study and understand about spar placement and sizing and how to build up the sort of bulkheads and stringers to achieve a desired shape you can apply these structural patterns to any shape you wish. So I'd suggest you study a lot of various plans.

You can find a lot of such plans to look at by simply googling for "model airplane plans download" or "free model airplane plans" or similar combinations of keywords. Sadly if you do so you're not going to find a lot of ducted fan jet designs to work with. So it's likely you will need to find a proven shape that was made in foam or some other material and then adapt it to balsa construction.

Now, as to your situation....

As a student of aeronautical studies I would expect that you've read about the design process for a number of advanced fighters. The one thing that they all have in common is that the plane is designed around the capabilities and sizes of the power plant. Aeronautical history is full of stories of planes which either had to be cancelled due to failure of the power plants to reach the light of day or planes which did not perform as promised when delays in the promised power plants resutled in lesser engines being used pending the availability of the final engines.

So the engine, or in this case the motor and fan, are the very first thing you have to pick out and tell us about. Once you've selected a motor and fan it'll be a lot easier to suggest something for an airframe. Until we know that it's impossible to suggest anything other than vague generalities.

Once you have a handle on the power system and the sort of size and weight that is mandated by the capability of that power system you can begin to figure out what sort of model you want. Personally I would suggest that you study a lot of the foam ARF designs and simply closely copy one which you can write up a good story to suggest application to full size, as much a work of fiction as it would be, and simply adapt some balsa structure to the foam shape. Since you're starting with so little background of your own relying heavily on this manner of plagarism will give you a decent expectation of success.

Simply put I know of precious few jet like models that have been done in balsa style construction. The smaller simpler stuff is typically done in foam mostly. And the bigger stuff almost always uses a balsa skinned foam wing with fiberglass fuselage. So like it or not you will very likely have to spend some time CAD'ing something into creation even if it's just to apply some example structures from prop driven sport models over to a jet planform..

Originally Posted by dave1211

Well actually i have made an aircraft twice already for my diploma and in my previous semester as well. The difference was that earlier it was in groups so things were much easier and we did give it to a professional to make..we also asked someone tol fly it for us..so building is not really that much of a problem......

Given what I see in the bolded parts of your post from earlier I would suggest that you have not actually made anything yet. At best you were involved in a partial way and largely as an observer. As such you are biting off a very large mouthful at this point. The best way to do this is start at the beginning. It's simply not a case of asking us for some plan when the range of such plans covers everything from some little 12 to 18 inch span "parkjet" up to a 10 foot span twin turbine mega model.

To summarize the first steps of your project for you I'd carefully consider these steps;

• Pick a power system. That's what the full size designers do and it's what you should do.
• Come up with a size and weight that is in harmony with the power system performance. Much of this is based on what worked before for others. Finding examples of size and weight for your power system is valid research. Asking us for suggestions and letting us know what the power system will be is also valid.
• If your project is primarily aimed at a full size craft which you will then "model" you will need to establish a cover story for the full size version. This cover story would have to include realistic allowances for fuel load, full size turbine engine, weapons loadout and delivery systems, radar system, radar countermeasures systems and some suitable story about the "compromises" made and why if you drop or limit any of these items. Those items that are needed to complete the mission are what is considered to be the "payload" that you didn't seem to understand.

Personally if this were something I was working on I think I'd go for the idea of an unmanned fighter drone. Since it's a work of fiction you could propose that it is based on the use of a tight beam encoded data link of some form between the RFD (Remote Fighter Drone) and the pilot situated at some remote facility. This would allow you to greatly de-emphasize the need for a shapely and complex to build fuselage. And in fact given the minimalist blended nature of the low radar signature designs you could get away with a flying wing concept that has a blended wing shaped center section as the "fuselage" to house all the payload components very easily. This could really aid in easing your design workload in terms of a wing shape and suitable structure.

wow that was a lot of info..thx a lot man...guess i'll have to search up some foam models...but i don't have the slighest knowledge of autocad even as we had someone to that for us as well...that is why i wanted readymade balsa plans..why is it that there are so few balsa designs?...but regarding the rest i'll follow what u said..thks again mate

Originally Posted by wizard of odd

That Nigel Hawes Tornado is looking better and better methinks.... will do well with a bit of tweaking to make it "unique". You may even be able to do a swing wing version.

Dang, I just ordered MYSELF a set of the plastic bits (and a Blenheim and a Sea Fury plan) and see I don't even need to do a project for Uni!

So long and ta-ta, I'm off to the shed to dig up the plan.... see ya all in a couple of weeks- and I don't give a damn if the damn 'roos are eating up the front lawn (again) in the meantime!

Odd

do u have the plan mate?..if you could give it to me i'd be very grateful

You're in a senior design project but have never designed or built anything by yourself, and you had somebody else do previous CAD, construction and piloting for you?!?! What DO students actually learn to do in college these days?!?!

Either I'm very confused because this doesn't add up, or something is very wrong.

Andy

Sorry but if in your last project you had someone to draw the plans (i.e. do all the CAD work), someone else to do all the building and someone else to do the flying what exactly was your team's role in the project ?

Anyway you could always try the Profili site, http://www.profili2.com/eng/default.htm look under Plans and Drawings. There are several hundred free aircraft plans there. You might find the odd one of some interest. But to be honest apart from the old small free flight Jetex models I really can't think of any wooden construction jet fighter plans anywhere.

Steve

Originally Posted by dave1211

do u have the plan mate?..if you could give it to me i'd be very grateful

Sorry, but I don't hold the copyright to the plans. If you follow the link listed above, I think it's only about 12 Pounds from the publishers of the RCM&E magazine.

Probably because the modern decently effective electric ducted fan and motor setups only came out after the move away from traditional frame and stringer balsa and tissue builds and foam had taken over.

There are a few plans for Jetex models and later free flight Rapier powered models. But without exception they are all far too small for what you want. And the structural details don't simply scale up directly.

What you are learning here is what I said in my first post. This is NOT by any means a simple task you've been set on. There's a mass of size specific factors that you simply do not understand in the aerodynamics, structural, control systems and power plant systems that are not something you can pick up in "one easy to type out chapter". The knowledge you need to produce what you want would easily fill a sizeable book. Never mind the skills needed to build and fly the creation that you are looking to design.

Hence my frustration at folks that think this whole "toy airplane" thing is so easy. The truth of the matter is that despite how simple some of them LOOK we are actually designing and building REAL airplanes that simply happen to be too small to ride in. The issues we have to solve are very much are the same as designers of full size aircraft.

Dave,

You should watch Flight of the Phoenix (the original one is better). Wait for the line, "He's mad, Lou!"

Then you'll understand what Bruce is saying.

Andy