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Pilot-34

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I’ve spent a lot of time looking At the remains of a old Cessna-210 laying on the ground.
I keep seeing a flying boat.
The engine is missing and there’s a folding chair where it was so it’s easy to envision the cockpit there,perhaps something resembling a WII bomber glass nose.
At one point a couple of boards laying against the wings. Looked like props to me.

What would it take to
1 bury 200-250 hp in the fuselage with drive shaft drive to a prop on each wing.
2 build a cockpit ahead of the firewall.
3 Add a water planing shape to the bottom of the. Hull.
4 whatever else I’m not thinking of to make it work.

Now please don’t tell me it can’t be done.
I know it can.

Tell me X will cost $xxx and weigh x and take xxx man hours.
In other words tell me about the challenges and let me decide if it’s impossible FOR ME.
 
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TFF

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If you can do every bit of fabricating without help and you doing all the real engineering, $100,000 and 4000 hours of no slouch Construction work. $300,000 if you add help.
 

Chilton

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Since the 210 normally uses 300 HP for takeoff, and since 2 props will be less efficient than 1 long prop on the front I suspect you need a lot more power than 250 buried in the fuselage. Even more so as a hull shape will add drag compared to the original shape.
 

Pilot-34

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Lol I’m sure the village children have shot this plane down and bailed out at least a million times
 

wsimpso1

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Let's see, you will be adding a seaplane hull, building new load bearing structures for cockpit, engine mount, and prop drive systems, then designing new gearboxes and driveshafts to get power to the wings. After that you will have to re-design much of the control system, re-design the fuel system around the adjusted prop positions, then build this largely new airplane. That is about as big a job as Cessna did to design the 210 in the first place.

To do so will require skills in design of airframe, boat hull, controls, fuel systems, gearboxes, shafts, and prop systems.

Good luck.

Billski
 

Pilot-34

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Since the 210 normally uses 300 HP for takeoff, and since 2 props will be less efficient than 1 long prop on the front I suspect you need a lot more power than 250 buried in the fuselage. Even more so as a hull shape will add drag compared to the original shape.
I am pretty sure that this plane originally flew with 260 horses.
Will two propellers that can sweep more area than the original be less efficient than one long propeller?
 

BJC

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If you can do every bit of fabricating without help and you doing all the real engineering, $100,000 and 4000 hours of no slouch Construction work. $300,000 if you add help.
Tom:

I think that you are way too optimistic. Engine buried in the fuselage with drive shafts to propellers on the wings? Flying boat? Relocated cockpit / panel / controls in a boat?

The only things salvageable from the C210 will be the outer wing panels and the door handles, and I’m not certain about the door handles.

OP:

Yes, you can do it if you have enough time, money, time, engineering skills, time, machining and fabricating skills, time, tools and workspace. And when it is done, you will have a grossly underpowered, overweight, underperforming, one-of-a-kind airplane worth much less than the cost of the engine alone.

I say go for it; lots of pictures, please, in your build thread.

BJC

PS. What are you drinking? I like your sense of humor; it is certain to ellicit some entertaining replies.
 

Pilot-34

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Let's see, you will be adding a seaplane hull, building new load bearing structures for cockpit, engine mount, and prop drive systems, then designing new gearboxes and driveshafts to get power to the wings. After that you will have to re-design much of the control system, re-design the fuel system around the adjusted prop positions, then build this largely new airplane. That is about as big a job as Cessna did to design the 210 in the first place.

To do so will require skills in design of airframe, boat hull, controls, fuel systems, gearboxes, shafts, and prop systems.

Good luck.

Billski
Yes you are correct Those were the Givens the question is how do I solve those problems?
 

Pilot-34

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Tom:

I think that you are way too optimistic. Engine buried in the fuselage with drive shafts to propellers on the wings? Flying boat? Relocated cockpit / panel / controls in a boat?

The only things salvageable from the C210 will be the outer wing panels and the door handles, and I’m not certain about the door handles.

OP:

Yes, you can do it if you have enough time, money, time, engineering skills, time, machining and fabricating skills, time, tools and workspace. And when it is done, you will have a grossly underpowered, overweight, underperforming, one-of-a-kind airplane worth much less than the cost of the engine alone.

I say go for it; lots of pictures, please, in your build thread.

BJC

PS. What are you drinking? I like your sense of humor; it is certain to ellicit some entertaining replies.
why can’t I use what’s there ?
From staring at it all these hours it would seem like the only things I couldn’t use would be the windshield ,landing gear and perhaps those all important doorhandles?
 

Pilot-34

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If you can do every bit of fabricating without help and you doing all the real engineering, $100,000 and 4000 hours of no slouch Construction work. $300,000 if you add help.
Could you itemize those figures for me please?
 

Wanttaja

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Let's see, you will be adding a seaplane hull, building new load bearing structures for cockpit, engine mount, and prop drive systems, then designing new gearboxes and driveshafts to get power to the wings.
Complete redesign of the wings, I think. Not only do they have to handle a thousand pounds or so of thrust in an area they weren't designed to handle, the plane will need floats near the wingtips to keep the plane level on the water. Stock 210 wings won't take the former, and they DEFINITELY won't take the latter.

Add to that is the fact that the carry-through structure in the fuselage isn't designed to handle either set of loads, either.

So... new wings: Check. New Fuselage: Check. Can't use the engine, won't use the original landing gear. Vertical stabilizer and rudder will need to be redesigned to handle asymmetric thrust if half the gear box fails. Horizontal stabilizer and elevators *might* be re-usable, though the stabilizer should be moved upward to get it out of the spray.

You *might* be able to re-use the aft fuselage cone...that's about it.

It'd be cheaper and take less time to design an amphibian from scratch. Check out the Gweduck for an example. IIRC, it took them ~15 years and ~$1M....and that was using a lot of Boeing Engineer friends for free design help.

Ron Wanttaja
 

BJC

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why can’t I use what’s there ?
From staring at it all these hours it would seem like the only things I couldn’t use would be the windshield ,landing gear and perhaps those all important doorhandles?
I would not use a windshield; an open cockpit will be much easier to get out of from 20 feet under water.

Skip the L/G too; make it strictly a flying boat.

Door handles will not be needed for an open cockpit.

Pour another one, and enjoy.


BJC
 

Pilot-34

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Complete redesign of the wings, I think. Not only do they have to handle a thousand pounds or so of thrust in an area they weren't designed to handle, the plane will need floats near the wingtips to keep the plane level on the water. Stock 210 wings won't take the former, and they DEFINITELY won't take the latter.

Add to that is the fact that the carry-through structure in the fuselage isn't designed to handle either set of loads, either.

So... new wings: Check. New Fuselage: Check. Can't use the engine, won't use the original landing gear. Vertical stabilizer and rudder will need to be redesigned to handle asymmetric thrust if half the gear box fails. Horizontal stabilizer and elevators *might* be re-usable, though the stabilizer should be moved upward to get it out of the spray.

You *might* be able to re-use the aft fuselage cone...that's about it.

It'd be cheaper and take less time to design an amphibian from scratch. Check out the Gweduck for an example. IIRC, it took them ~15 years and ~$1M....and that was using a lot of Boeing Engineer friends for free design help.

Ron Wanttaja
lol OK once again you have identified the problem but you haven’t told me what it’s gonna take to fix them.
So far most of what has been pointed out seems to be minor problems requiring the addition of a little metal.


Now if I could just get an idea of how much metals involved. Or are you telling me the structure there would handle 200 hp but not 260?
I think I could deal with 200 hp.
 
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Wanttaja

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Could you itemize those figures for me please?
Let me take a stab at it.
Category
Engineering Hours​
Rate​
Construction Hours​
Rate​
Materials​
Subtotal​
Wings
2000​
$75​
1000​
$45​
$20,000​
$215,000​
Engine/Gearbox
4000​
$75​
1500​
$45​
$30,000​
$397,500​
Fuselage Mods
1000​
$75​
500​
$45​
$20,000​
$117,500​
Tail Surfaces
250​
$75​
500​
$45​
$5,000​
$46,250​
Seaplane Mods
1500​
$75​
1000​
$45​
$50,000​
$207,500​
Test
1000​
$75​
500​
$45​
$10,000​
$107,500​
9750​
5000​
$135,000​
Monthly Rent​
Duration​
Facilities
$2,000​
24​
$48,000​
Total
$1,139,250​

Just a SWAG. Labor costs are roughly what Boeing pays its employees, however, the ACTUAL rate (what the company actually shells out) is typically ~twice that (medical, pension, etc.).

Personally think some of the engineering hours are low (a single labor year for the wings? Ha!) and I'm guessing the engine/gearbox will be much more expensive as you'll be starting over several times.

Ron Wanttaja
 

BJC

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lol OK once again you have identified the problem but you haven’t told me what it’s gonna take to fix them.
So far most of what has been pointed out seems to be minor problems requiring the addition of a little metal.
Now if I could just get an idea of how much metals involved.
Love it! But I’m out. Enjoy.

BJC
 

Angusnofangus

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lol OK once again you have identified the problem but you haven’t told me what it’s gonna take to fix them.
.
Let's see, what will it take? Money (lots of it), time (lots of that, too), engineering expertise (buckets full), and a whole whack of persistence. I think that a clean slate would be a better avenue to pursue
 
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Pilot-34

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Let me take a stab at it.
Category
Engineering Hours​
Rate​
Construction Hours​
Rate​
Materials​
Subtotal​
Wings
2000​
$75​
1000​
$45​
$20,000​
$215,000​
Engine/Gearbox
4000​
$75​
1500​
$45​
$30,000​
$397,500​
Fuselage Mods
1000​
$75​
500​
$45​
$20,000​
$117,500​
Tail Surfaces
250​
$75​
500​
$45​
$5,000​
$46,250​
Seaplane Mods
1500​
$75​
1000​
$45​
$50,000​
$207,500​
Test
1000​
$75​
500​
$45​
$10,000​
$107,500​
9750​
5000​
$135,000​
Monthly Rent​
Duration​
Facilities
$2,000​
24​
$48,000​
Total
$1,139,250​

Just a SWAG. Labor costs are roughly what Boeing pays its employees, however, the ACTUAL rate (what the company actually shells out) is typically ~twice that (medical, pension, etc.).

Personally think some of the engineering hours are low (a single labor year for the wings? Ha!) and I'm guessing the engine/gearbox will be much more expensive as you'll be starting over several times.

Ron Wanttaja
SWAG ? So no actual information ?
What are your qualifications to make this guess ?
For instance how many planes of above this size weight and complexity have you been responsible for the engineering on?
 

BBerson

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Salvage wings are not normally eligible for an EA-B Airworthiness certificate. Exhibition might work, but depends on how much you want to play with the regulators.
 

Wanttaja

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SWAG ? So no actual information ?
What are your qualifications to make this guess ?
For instance how many planes of above this size weight and complexity have you been responsible for the engineering on?
Lead engineer for several small spacecraft development and flight programs, lead engineer for a batch of small spacecraft proposals, including primary responsibility for assembling engineering quotes and estimating material costs. The spacecraft were all low-complexity, secondary payloads where the Government waived most of the quality and engineering standards normally required. In other words, simpler than this project. The last 20 years of my engineering career involved repeated cases of doing exactly this sort of estimate.

Aircraft experience included systems engineering on small manned/unmanned reconnaissance aircraft using a Continental IOL-200 engine, and a bit of experience on the P-8 Orion (albeit just in the system requirements verification field).

One thing I did miss on the table above...tooling costs. You'll have the need to acquire CAD/CAM tools, forges, milling machines, welders, etc.

So, what's your basis for claiming I'm wrong? Do you disagree with my assessment that the wings would need a complete re-design?

Ron Wanttaja
 
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