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-   -   Proposed Fiberglass RC Airplane with a 1.5hp diesel engine. (https://www.rcuniverse.com/forum/beginners-85/11675252-proposed-fiberglass-rc-airplane-1-5hp-diesel-engine.html)

aureliocr 02-13-2020 02:49 PM

Proposed Fiberglass RC Airplane with a 1.5hp diesel engine.
 
My school proposed as a project to create an RC aeroplane using a Super Tigre GS40 engine that's gathering dust in a corner. The model is based on Tom Hunt's Vertigo from 1994. The wingspan is approx 76 inches and the length 56 inches given our calculations. The engine weighs around 400 grams. We are thinking of using 2 electric motors on the wings that generate each at around 500kvs.

We're unsure of what materials we want to construct it with, we are currently thinking of a fibreglass body with balsa wood reinforcements but we don't know how fast the weight of it can increase. We simulated it in SolidWorks with an all balsa wood construction and it weighed around 1.5kg but we're afraid it might be too fragile. What are the pros and cons of using a fibreglass construction when you factor in our weight and dimensions?


init4fun 02-13-2020 04:45 PM


Originally Posted by aureliocr (Post 12582936)
My school proposed as a project to create an RC aeroplane using a Super Tigre GS40 engine that's gathering dust in a corner. The model is based on Tom Hunt's Vertigo from 1994. The wingspan is approx 76 inches and the length 56 inches given our calculations. The engine weighs around 400 grams. We are thinking of using 2 electric motors on the wings that generate each at around 500kvs.

We're unsure of what materials we want to construct it with, we are currently thinking of a fibreglass body with balsa wood reinforcements but we don't know how fast the weight of it can increase. We simulated it in SolidWorks with an all balsa wood construction and it weighed around 1.5kg but we're afraid it might be too fragile. What are the pros and cons of using a fibreglass construction when you factor in our weight and dimensions?

If this is to build a non flying static display model the strength won't matter , and if this IS to be a flying model and you have no expert RC airplane pilot to fly it , it won't matter either .....

CESSNA 421 02-14-2020 05:00 AM

Beginners in RC start here for help
 
I love init4fun's response: "If this is to build a non flying static display model the strength won't matter , and if this IS to be a flying model and you have no expert RC airplane pilot to fly it , it won't matter either."
In a way that about sums it up for all R/C model building.

jester_s1 02-14-2020 12:27 PM

Start with something that has been proven to fly well. A Sig Kadet Senior is a good choice. Then you can move into more experimental designs.

DGrant 02-16-2020 12:08 AM

It sounds like a "trial by fire" proposal your school gave you. I'm not getting from your post that you know much if anything about aircraft design, or how to build or fly any particular type of model.

I looked up the Vertigo in a Google search, and found this link... https://www.rcgroups.com/forums/show...years-later%21

It looks to be a follow up on the original design... It also looks like the gentleman worked for years on it to get it where it's at in the article(which the article in the link is 16yrs old). The model does look to be a somewhat proven design, but also very advanced, in every way. Not only development and construction, but also takes a very knowledgeable experienced pilot, of which even most seasoned modelers wouldn't be able to conquer... at least without a firm commitment and hours/days/weeks/months of study and work. It's a huge undertaking.

I hope you and your school understand what you/they're contemplating is a project that could literally take years, especially if nobody has any modeling experience. If they did, they would know without a doubt what the process of creating such model would entail. How long are you going to be going to that school?... Do you plan to see it through?.. It could take quite a while. Some of use in the real world with alot of experience are known to work for a few years or more on one plane...and that's with planning and experience..Even mainstream kit building takes considerable time.

As for material... Fiberglass will weigh far too much to do the whole frame.. The wings and tail must be light.. as light as humanly possible. With experience though(there's that word again), balsa can be built into some seriously strong structures. There really is no need for fiberglass though.. Its a .40 size engine, with maybe a few electric motors..so it won't have immense power, or much vibration... What you described for power is just something to create thrust..

I suggest further studying the Vertigo, and really looking at how long that process took... and what your resources are (consider everything..equipment, tools, and especially experience).... it's the experience factor that will dictate most everything. Really there's helpful people around these sites... but most of us aren't going to write it all down for you.. and it wouldn't matter if we did...The fact is, it's all already been written, you just have to study and figure out if it's even possible to create something like what you're contemplating. Good luck with it.


jester_s1 02-17-2020 04:12 PM

To the OP: What grade are you in? And what is the actual situation? Is this going to be for a grade, or is it an enriching project as part of an after school club?
I ask because I'm a middle school engineering teacher. I design problem solving and design projects all year long for kids and teach them the fundamentals so they can be successful. I would never tell a group of high school students to try and design an airplane when they've never flown one. Aeronautics is a complicated science with a lot of variables working at the same time. Even if everyone in your group already knew model building techniques, your chances of producing a successful scratch design would be virtually zero due to all of the interrelated issues to deal with.
If the point is for the group to work together and get something in the air, take the advice above and build one of the classic trainers like the Kadet Sr. and then get a qualified flight instructor at a proper flying facility to train you.

aureliocr 02-18-2020 08:56 PM

We're aerospace engineers but this is our first big project combining aircraft design, modeling, and construction. The design part of this project has been happening for about a year and we're starting to get into modeling and construction. We feel we need a bit (a lot, actually) of help in this part of the project.

I've attached a render of our proposed design, which has been tested in Solidworks and ANSYS.

We realize we are a bit over our heads because we are in no way experts in any area, I haven't even mentioned we are trying to give this aircraft VTOL capabilities... but I don't even want to get to that part lol.

Anyways thank you for your response, we are currently starting to research more about balsa wood construction.

EDIT: I can't upload any photos until I have 10 posts, kind of a dumb rule tbh.

aureliocr 02-18-2020 09:03 PM


Originally Posted by jester_s1 (Post 12583807)
To the OP: What grade are you in? And what is the actual situation? Is this going to be for a grade, or is it an enriching project as part of an after school club?
I ask because I'm a middle school engineering teacher. I design problem solving and design projects all year long for kids and teach them the fundamentals so they can be successful. I would never tell a group of high school students to try and design an airplane when they've never flown one. Aeronautics is a complicated science with a lot of variables working at the same time. Even if everyone in your group already knew model building techniques, your chances of producing a successful scratch design would be virtually zero due to all of the interrelated issues to deal with.
If the point is for the group to work together and get something in the air, take the advice above and build one of the classic trainers like the Kadet Sr. and then get a qualified flight instructor at a proper flying facility to train you.

We're college students studying aerospace engineering, I should've said that in the original post but I wrote it in a hurry.

We have all our calculations that back up our design and our different variables from our motors, I tried attaching a render of our design but I need to have 10 posts before I can do this.

We lack a lot of experience in the modeling and construction phase of this project, we really don't know if we want to use fiberglass or balsa wood. Our original thought was balsa wood would not be sturdy enough for the weight of our aircraft, but reading the replies on this thread has made us research more about balsa wood construction.

And yeah I completely agree with you about us having zero experience flying model planes...

DGrant 02-18-2020 11:10 PM

There's only one way to get experience, and reading about it won't get you there. As suggested, get a simpler model that's a proven design, and learn. There' so much you can learn by just building a trainer style model with about a .60" wing span... and your engine would even work in that.

What we're trying to tell you comes from experience. You're talking to experience right here in this thread. You can continue to ponder all of it, and keep trying to decide what kind of material to use, etc.. etc.. but when you actually build a model and fly it, therein lies some experience, and grow from that. Burt Ratan started with simple small designs of everything, even paper airplanes, then developed it from there.

If as you say you lack alot of experience is modeling and construction, buy a Sig Kadet and build that kit step by step, per instructions exactly and read every word... that's where you will read and learn and apply. Those types of kits all have great techniques and ideas, all you have to do is build a few to find out. That would even give you timelines of certain aspects of construction. At this point you have no clue how long it even takes different glues to dry.

Just build a plane, there's always something to learn. If you were to build a plane, you'd have something to get some flying experience as well. If you can successfully take a fully proven designed kit and build it, then get some instruction and fly it, you would know the degree of difficulty you're up against.. I can safely say myself and the other gentleman posting here probably know very well what you're up against, so I would advise you to heed the advice we're offering. It's good stuff.

I've built dozens of kits of different sorts, and I've said for years if a person really wants to learn about the finer aspects of building and construction, buy and build a kit from 5 different manufacturers, and pay close attention to the techniques each manufacturer/designer instructs the builder to do. If you did something like that, you'll end up with a small library in your heads of great techniques, and be on your way to aerospace engineering. If building kits sounds like it takes too long, you might be in the wrong class, because it takes what it takes. The end result is the goal, not how long it takes to get there.

PS... We're well aware of the original design being a VTOL... That's part of how we know what your facing. It's not a hill, It's a wall... get ready to climb if you want to get to the top. Good luck.

Hydro Junkie 02-19-2020 07:09 AM

I was just reading your design ideas and, as I see it, putting a nitro .40 in the nose and a pair of electrics in the wings is asking for problems. If one of the electric motors fail, you will see your design flat spin into the ground unless you're very careful. If one fails during the climb out, you may not have time to react. Something else to consider is that you are looking at having to carry a lot of weight, being both the electric motor battery packs and nitro fuel just for starters. You also have to consider the weight of a throttle servo for the nitro motor as well as twin electronic speed controls. A Futaba S3004 ball bearing servo weighs weighs 1.31 ounces(37.2 grams) of which you will need four or five minimum, two ESCs that will weigh one ounce each(that is the weight of a Castle Creations BEC2.0 15A BEC rated at 14S, just for sake of figuring weight), two battery packs(one for each motor) at 600 grams each(that's for a Revolectrix 5000mah 4S 70C Graphene Oxide GoPACKS, again just for figuring weight). Now, add to that the variable weight of your nitro fuel and you're carrying a fairly large load, BEFORE you add your receiver and receiver pack.
Just got to thinking. Others have said to buy and build a Sig Kadet Sr. I have to agree with that recommendation. Something to consider is that you are looking at a plane that's 56 inches long with a span of 76 inches at 3.3 pounds. That will be very "short coupled", meaning it could be "twitchy" in flight. The Kadet Sr has a 78 inch span and is 62 inches long. It has an estimated flying weight of 6 pounds, nearly double what you are trying to achieve. That also includes fixed tricycle landing gear so, subtract that and you would be looking at a plane that's still roughly 5.75 pounds and is a proven design. BTW, what I listed as weights in the previous paragraph totaled up to be 275.4 grams or .607 pounds of weight. You still need to add nitro fuel and the weight of your electric motors and all three motor mounts as well as the other hardware needed to that

Propworn 02-19-2020 03:27 PM

You are saying this is a college level project. Is there a specific goal for this project or is it a one time event. If the students are rather keen on a competitive level as most are then the SAEA Aerodesign Competition might be the answer. A team designs and builds the aircraft for a given task then they can have an experienced pilot fly it. I was the mentor/pilot for 8 years for the local u university and i must say we had a riot.

saeaerodesign.com

jester_s1 02-19-2020 03:34 PM

My club hosts the SAE heavy lift contest in Fort Worth every other year. I'm volunteering again this year. I was on the crash recovery team last time and probably will be again this year. I see some outstanding designs at that contest and also some of the most incompetent building you can imagine.

I'm going to be blunt here, just because I want to see you succeed in the long run.
If your team has been designing for a year and only now are getting around to thinking about building techniques, you've probably wasted most of that time. Design has to be done with building in mind. If your professors didn't explain that, they should really consider other employment.
But even if they didn't explain that, how could you possibly expect to create a good design from scratch without prototyping or testing anything? Surely you don't think that Solidworks wind tunnel sim is going to tell you anything?
Lastly, what kind of college junior or senior looking to graduate with an aeronautical engineering degree gets on an online forum to ask strangers to do their homework for them? Is this what you'll do if McDonnell Douglas hires you?

*rant over*

In the interest of helping you try to solve your dilemma: What's your timeline for getting a working prototype in the air? My suggestion is to look at plans for some of the classic pattern planes like the Joe Bridi Kaos. Those planes were designed to be fairly easy to build straight so they'd fly well with a minimum of fuss. Slab sided fuselages with foam wings aren't the lightest, but they are fast and will work. Also, search for an RC club in your area and make an appointment to work with a flight instructor. You'll not only build some piloting skills, but you'll also see what goes into a good flying plane.

Propworn 02-20-2020 05:13 AM

I disagree with Jester our first year of competition the three students on the team only received permission after the Christmas holidays. They decided on a flying wing built it and without a test flight drove from Windsor Ontario Canada to Frorida and won everything in the advanced class. Three months to design, build and write up a report. Students accomplish this on top of the regular class load

I have flown at both the east and west competitions and quite a few put their maiden flights on Friday the weekend of the competition.

By the way the field in Bembrook just outside Fort Worth is quite nice. I have two models of Chuck Cunnighams Lazy Ace and was quite surprised to see a plaque in his honor at the feild. Great group of guys and gals hosting the event.Flying over the water can be intimidating. If you happen to be in the area a trip to the stockyards for a steak dinner is a must.

jester_s1 02-20-2020 12:09 PM

Yes, Chuck Cunningham was a founding member of the Thunderbirds. I've been a member there 13 years.
I agree that lots of teams make their maiden flight at the contest. They sometimes do well. They usually don't.
Are you making the trip this year, Propworn? It would be nice to put a face with the profile.

Propworn 02-23-2020 12:35 AM


Originally Posted by jester_s1 (Post 12584382)
Yes, Chuck Cunningham was a founding member of the Thunderbirds. I've been a member there 13 years.
I agree that lots of teams make their maiden flight at the contest. They sometimes do well. They usually don't.
Are you making the trip this year, Propworn? It would be nice to put a face with the profile.

No after 9 years one of the first team members is an associate prof at the university and they have actually started an aeronautics program. The university prefers to use its own staff as advisers. I used to make a vacation out of it and took two weeks flying my own models at different feilds on the way down and back. That put the competition on the weekend in the middle of that two weeks. I have 8 weeks paid vaca every year now I load up the truck camper n trailer and the wife n I head out for a month or more and i visit clubs along the way. Last year we spent a month in Newfoundland this year not going as far but next year want to go to Tuktoyaktuk and float fly off the arctic ocean.

jester_s1 02-24-2020 05:52 AM

That sounds pretty great. My wife is the one in our family with the traveling bone. We plan to buy an RV when we retire in about 25 years and roam all over hell and creation. I'll have to make sure it has enough storage for a couple of planes.

Hydro Junkie 02-24-2020 06:49 AM


Originally Posted by jester_s1 (Post 12585098)
That sounds pretty great. My wife is the one in our family with the traveling bone. We plan to buy an RV when we retire in about 25 years and roam all over hell and creation. I'll have to make sure it has enough storage for a couple of planes.

Why wait? The wife and I had listened to many people say the same thing, only to find that when they retired, they:
1) Couldn't afford to buy one
2) Weren't able to use it due to declining health
3) Bought one and then found they couldn't afford to use it
4) Had too many other things to deal with to use it
We bought a 26ft camp trailer back in the fall of 2013 and started using it in March of 2014. Since then, the only states it hasn't been to yet are:
1) Alaska
2) Hawaii
3) North Dakota
4) Minnesota
5) Wisconsin
6) Michigan
7) Vermont*#
8) New Hampshire*#
9) Maine
10) Rhode Island*
11) Maryland*
12) Delaware*
13) New Jersey*
14) Oklahoma*#
15) Florida
16/17) The Carolinas*#
18/19) The Virginias*#
20) Maryland
Not too bad, 30 states in five years, something that we probably wouldn't have done if we had waited until we retired. Needless to say, many of the states the trailer hasn't been to the wife and I have. The only states WE haven't seen are marked with a *, the only ones I haven't seen are marked with a # :cool:

Propworn 02-24-2020 08:26 AM

When we bought our first truck camper it was an oldie but a goody took a summer to refurbish it. No washroom but a porta potty and portable shower tent for those off grid times we camped which was often. Eventually tried a motor home then a trailer and fifth wheel eventually back to the truck camper this time an Arctic Fox 811. Washroom, AC everything we needed in a small package allowing us to tow a 12 ft enclosed trailer for the toys. Smaller footprint allows us access you would never get to with any of the others and allows a toybox tow behind. This is a stop at the Humber club in Newfoundland this summer. You can see the F250 Super Duty, camper, trailer even the canoe on top of the trailer.


The camper is designed for a short box pickup the F250 has a 6.5 ft bed as you can see there is lots of room for the two of us and one cat who likes to travel.



Hydro Junkie 02-24-2020 08:38 AM

Sounds familiar, first one my family had was a 10ft Chinook camper on a beefed up 1967 Ford F-150. Was the same thing, porta potty and small water tank with a hand pump at the sink. Was totaled a few years later when the differential exploded while my father was driving down the freeway. He ended up wrapping it in roughly 100ft of chain link fencing while taking over a hillside. Left rear corner of the camper was smashed in, truck frame was damaged beyond repair and my father got away with bruises and a bruised ego. Only had one other RV trip after that, in 1973 he rented an 8ft Six Pac camper and put it on his 1963 Chevy C-10 that replaced the Ford. Took it on a two week trip across Washington and BC, got home and took it back after washing it. My trailer is the first RV anyone in the family has had since

DGrant 02-24-2020 08:33 PM

RV's are great! We bought our Class-C a few years back and have been traveling and flying it up everywhere. A utility trailer to tow is the only way to go, you can carry many planes and toys without hassling putting them inside your rig. Our rig is only a 31' so we can still get most everywhere we want with no problem. I''m into my second year IMAC at this point, and just lovin life.

Don't wait 25yrs!! Just do it. I only wish I would have done it 25yrs ago, because there's things I would have liked to do then that I can't do now.. it's still a blast though.

Hydro Junkie 02-25-2020 06:26 AM

Here's a link to a video on mine. There's a few insignificant variations but it's pretty much what mine looks like.
And here it is, first road trip, before I had totally dialed in the equalizer hitch:
https://attachment.outlook.live.net/...animation=true


jester_s1 02-28-2020 05:00 AM

Well we aren't doing it now because we both work at jobs we like full time and then some, so it wouldn't get used much. We are also planning to upgrade houses next year and are saving for our daughter's college. So we do have a plan. It's just that big toys don't fit into that plan for now.
We may pull the trigger on it sooner, like after my daughter graduates college. That would be in about 10 years.

Propworn 02-28-2020 06:28 AM

Sounds like you have a plan. One thing you can do is to rent some and try out a couple different platforms. Motorhomes are easy to rent as are trailers. I know in Canada if you head west to the mountains you can rent a camper truck combo in BC. Iwould think you could find something similar in the US.
Find out what you like and the size buy once. Many make the mistake of buying one thi g and after a few trips wish they had purchased something else.

Hydro Junkie 02-28-2020 08:46 AM


Originally Posted by Propworn (Post 12586042)
Find out what you like and the size buy once. Many make the mistake of buying one thi g and after a few trips wish they had purchased something else.

This is very true. Some go right to the biggest diesel pushers or 5th wheel trailer they can find thinking "I'll have room for everything I'll ever need" only to discover that they can't take it anywhere because it won't fit. Many campgrounds can't handle anything over 30 feet long due to tight turns and limited space. I've watched a diesel pusher, due to it's weight, sink into blacktop when supported by it's auto leveling struts.
The biggest thing to think about is "What do I really need to take with me when I hit the road?"
Funniest thing I've seen is a couple that had gone out and bought a 40 foot 5th wheel, a new one ton truck to pull it with and had never had an RV before. The wife and I had arrived at the campground 45 minutes earlier and had already set up our site and were eating lunch. The "rookie couple" pulled into the site next to ours, got out of their truck and started trying to figure out what to do next. To say it was a comedy of errors would be an understatement. The sequence off events went something like this:
1) Pulled into the site, leaving the rear 6-8 feet still in a drive area. Rookie wife asked husband if she could run out the slides. I went out to help them out
2) Had rookie husband pull rig ahead to clear drive area, asked if he had anything to level it with, met with blank stare and "What do you mean by level it?" Rookie Wife asks again, "Can I run the slides out?"
3) My wife brought out a small level that I placed on the floor of the new rig, found it was almost a "bubble" low to the right. Rookie husband found some interlocking leveling blocks in a storage compartment, showed him how to level the rig. Rookie wife asks again, showing frustration, "Can I run the slides out?"
4) I told rookie husband to disconnect the truck(it was blocking the drive area in at the other end of the site), only to have him start to do so without extending landing gear first. Stopped him from dropping the trailer on the ground and helped him unhitch the trailer. His wife asks again "Can I run the slides out yet?" now getting seriously aggravated
5) I asked the rookie husband if he knew how to hook up the trailer to power/water/sewer? Rookie husband tells me he can't hook up to water as it will over fill his water tank and shore power will damage his batteries, both not true. Explain to him how the trailer is set up and how to hook everything up. Rookie wife decides she's not going to wait any longer and runs out slides, forcing rookie husband to have to crawl under slides to hook up trailer to power/water/sewer connections.
6) Rookie husband finishes hooking up utilities but has the sewer hose laying on the ground, meaning it won't drain properly. I show him a support I have for my sewer line, only to find he had bought one but didn't know what it was for. Installed the support for him as he watched
7) Rookie wife asks rookie husband to set up her "kitchen". My wife and I look at each other confused as the kitchen should be set up 'inside the trailer". Come to find out, they had been watching You Tube videos on what they would need. EVERY STORAGE AREA WAS RAMMED FULL OF STUFF!!!!!!!! Wife and I watched as he pulled multiple camp carpets, multiple tables, multiple camp stoves, electric coffee pots, several folding chairs and who knows what all else out of the various storage areas. Two hours later, he's finally done and I, being the helpful person I am, take a walk around their trailer. With all the stuff he had pulled out, most of the storage areas were still full. When I asked why they had so much stuff, I was told that the internet said they would need it all for a month long trip. At this point, there wasn't much I more I could do except give him the following advice; You need to do two things when you get home:
1) Unload EVERYTHING you have in the storage compartments and only put back the things you actually used this trip
2) Take another SHORT trip, and see what you use or miss on that trip. Anything you don't miss that was left at home or wasn't used on the short trip doesn't go back in to the trailer as all that weight is hard on the truck and trailer

Just got to thinking, that was back in 2014, at a KOA in Spokane Washington. I wonder how much they took out of the trailer and, more importantly, are they still married? All she could think about was running out the slides and her own comfort. If things didn't change, I'd be willing to bet they either don't still have the rig or are divorced because of it

jester_s1 02-28-2020 01:20 PM

I honestly had not thought of that. But it makes sense. 2 or 3 weekend rentals would be worth many times the cost in getting the purchase right the first time.


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