Hurricane Mk103

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

WBNH

Well-Known Member
Joined
Oct 5, 2006
Messages
309
Location
Portsmouth, NH
Minor interruption of the 103 part of this thread...

Maybe it's been mentioned, but it's news to me...youtube just alerted me to a new movie coming out this fall regarding the 303 squadron, titled Hurricane. [My great uncle was flying a Hurricane with the 504 sq, lost 5/14/40 -- Battle of France.] The trailer if it interests anyone: https://www.youtube.com/watch?v=IV5e2HA6XkU

Sorry for the drift.
 
Last edited:

pictsidhe

Well-Known Member
Joined
Jul 15, 2014
Messages
7,377
Location
North Carolina
I think I may, in time, be able to forgive you ;)
Sounds interesting. 303 was the highest scoring squadron of the Battle of Britain. They flew Hurricanes, not the 'saviour' Spits...
My Grandad was a warehouse storesman in the Mediterranean in WWII. Invalided out with a 2" shortened leg after his warehouse was bombed. Oh, well, my mother and two aunts wouldn't have been conceived if he hadn't been sent home early...

Edit, I need to check with Mumsy how short that leg was. He had one hell of a limp.
 

radfordc

Well-Known Member
Joined
Feb 5, 2008
Messages
1,339
This isn't about replicating the airfoil, it's about replicating the behaviour of the whole wing.
I find it fascinating that you expect to duplicate a Hurricane's behavior in an aircraft that weighs 254 lbs! Fascinating!
 

cluttonfred

Well-Known Member
HBA Supporter
Joined
Feb 13, 2010
Messages
7,154
Location
World traveler
I agree with radfordc. pictsidhe, spend some time watching YouTube videos of Loehle 5151 Mustang and P-40 "replicas." They sure look like fun in a Walter Mitty way, but they lighter than a J-3 Cub and fly that way. Your "Hurricane Mk103" would have to be *half* that weight and is going to fly like an ultralight not a WWII fighter. Take just the look of a Hurricane and then design the best ultralight you can around that shape and you'll have a safer, more enjoyable plane in my opinion.

I find it fascinating that you expect to duplicate a Hurricane's behavior in an aircraft that weighs 254 lbs! Fascinating!
 

ScaleBirdsScott

Well-Known Member
Joined
Feb 10, 2015
Messages
1,201
Location
Uncasville, CT
Well, if anything, spend time looking at the Hummel Ultracruiser. It's mostly wing! The rest of the plane is rather tiny. And spartan. But, it does seem like fun, for what it is.

Trying to build something even close to the size of the Loehle replicas is fine but I still don't think it makes sense at anything approaching the part103 regime. The 5151 is 22ft long with a 27ft wingspan... huge compared to a Hummel or a Mini-MAX or similar.
 

pictsidhe

Well-Known Member
Joined
Jul 15, 2014
Messages
7,377
Location
North Carolina
I find it fascinating that you expect to duplicate a Hurricane's behavior in an aircraft that weighs 254 lbs! Fascinating!
Don't worry, I have no delusions whatsoever of ever hitting 300+mph with the wings and maybe tail still on. I think I may manage a couple of g sustained turn if I have 40hp. What I really don't want to do is build in a tip stalling tendency. The Hurricane had reasonable manners, I want those manners. I know I won't get the speed and the excitement level is going to be, well, a lot less. Unless, of course, I can screw up the balance so the edges of the envelope turn into a drop into the bowels of spinning hell.

Plagiarism is easier than blank sheet design. Once I know the angles that the root and tip Hurricane airfoils stall at, I can build a 103 that behaves similarly, if much slower.
If I was building a FW190, I'd still want to know what airfoils it used, but I'd change things to try and reduce its vicious stall, by getting the inner wing to stall sooner.
 

cluttonfred

Well-Known Member
HBA Supporter
Joined
Feb 13, 2010
Messages
7,154
Location
World traveler
One idea that occurs to me when trying to scale down a single-seat fighter is to treat the canopy like a bubble for the pilot's head only and hide the rest of the reclining pilot below the canopy rails and forward all the way to the seeming firewall (actual firewall would be more forward). It works better with something with a fairly rearward cockpit like the Corsair or the Saetta:

Screenshot 2018-08-15 at 10.38.43 PM.png
 

pictsidhe

Well-Known Member
Joined
Jul 15, 2014
Messages
7,377
Location
North Carolina
One idea that occurs to me when trying to scale down a single-seat fighter is to treat the canopy like a bubble for the pilot's head only and hide the rest of the reclining pilot below the canopy rails and forward all the way to the seeming firewall (actual firewall would be more forward). It works better with something with a fairly rearward cockpit like the Corsair or the Saetta:

View attachment 73602
That was plan A. Unfortunately, my eyes would only be 2" above the bottom of the windscreen. I am going to sacrifice scale for a better view with a taller canopy. Which will still only have my head in it...
To stop it looking too enlarged, I could shift the canopy rails up a bit, too. Canopy opening will probably extend below the plexi part (or I paint some plexi) to give better cockpit access. The full size Hurricanes had in flight adjustable seats. the pilots would open the canopy and jack the seat up for landing. An acme screw arrangement like full size would be very heavy, but an inflatable seat cushion would be way lighter...

A 103 with the pilot behind the wing is going to be very tricky to get a safe cg on.

If anyone has a good source of glider seating pics, I am having trouble finding any.
 

Tiger Tim

Well-Known Member
Joined
Apr 26, 2013
Messages
3,092
Location
Thunder Bay
That was plan A. Unfortunately, my eyes would only be 2" above the bottom of the windscreen. I am going to sacrifice scale for a better view with a taller canopy.
Crazy Plan B: do your Hurricane in one of the all-black schemes so some portion of your cockpit side walls can be dark tinted plexi.
 

pictsidhe

Well-Known Member
Joined
Jul 15, 2014
Messages
7,377
Location
North Carolina
Hmmm, how would you do that with paint, clearcoat spots before spraying? Perforated sheet would make a great mask for that. Paint, then sand through the paint to clearcoat.
 

billyvray

Well-Known Member
Joined
Aug 17, 2005
Messages
742
Location
Newnan, GA
Any thoughts on a totally unscale warbird - cartoon scale? Fat body little thing would be too cute. This is an RC model.

fat spit.jpg


Bill
 

pictsidhe

Well-Known Member
Joined
Jul 15, 2014
Messages
7,377
Location
North Carolina
A 3/4 scale fuse width and height would change the cockpit from 'glove' to something I could sneeze in. That may happen. I'd have to go bigger for the cartoon effect, though. That would clearly be a fun sized fighter though.
 

cluttonfred

Well-Known Member
HBA Supporter
Joined
Feb 13, 2010
Messages
7,154
Location
World traveler
Isn't that a Fly Baby? (Ducking as Ron W. throws yet another empty whiskey glass....) ;-)

Wait a sec, that was Fritz, Ron is from the Northwest, maybe he throws coffee mugs. :p

Any thoughts on a totally unscale warbird - cartoon scale? Fat body little thing would be too cute. This is an RC model.

View attachment 73617


Bill
 
Last edited:

pictsidhe

Well-Known Member
Joined
Jul 15, 2014
Messages
7,377
Location
North Carolina
I've been flitting around a bit on this. I wanted to see if my Briggs engine idea is feasible, so I've been doing way too much TV recently ;) It looks like it will work, with effort. That gives me loads and loads of legroom! also been looking at control surfaces. I may have to tweak things to give enough force at the stick. With the same stick deflection, forces vary with the cube of scale. They also vary with the square of speed. a 2/3 scale Mk103 is only going to have a few % of full size stick forces, which is something I won't want to sneeze at... All the balances can easily go, then it gets a bit tricky. I think that extra reflex on plain differential ailerons may be the way to go.

Engine specs, revised slightly from 1938:
Type:
HTML:
del
Rolls Royce Merlin
HTML:
/del
Briggs & Stratton Vanguard V
HTML:
s
1
HTML:
/s
Capacity:
HTML:
s
26
HTML:
/s
.6 litres
Power
HTML:
s
10
HTML:
/s
40hp
Weight
HTML:
s
12
HTML:
/s
80lb

I have some more drawings on the way, including a set of main production wing profile drawings and ordinates. Jackpot!
 

pictsidhe

Well-Known Member
Joined
Jul 15, 2014
Messages
7,377
Location
North Carolina
I've been flitting around a bit on this. I wanted to see if my Briggs engine idea is feasible, so I've been doing way too much TV recently ;) It looks like it will work, with effort. That gives me loads and loads of legroom! also been looking at control surfaces. I may have to tweak things to give enough force at the stick. With the same stick deflection, forces vary with the cube of scale. They also vary with the square of speed. a 2/3 scale Mk103 is only going to have a few % of full size stick forces, which is something I won't want to sneeze at... All the balances can easily go, then it gets a bit tricky. I think that extra reflex on plain differential ailerons may be the way to go.



I have some more drawings on the way, including a set of main production wing profile drawings and ordinates. Jackpot!
 

radfordc

Well-Known Member
Joined
Feb 5, 2008
Messages
1,339
The Briggs engine I'm familiar with is way too heavy for any Part 103 airplane. This is the Vanguard engine at 125 lbs and to this you will also need to add a redrive and prop. And you're still getting less than 40 hp. There are many much better options available (Poloni, Hirth, Rotax, etc).

I have flown many ultralight planes and they all had acceptable stick forces. I don't think this will be a problem.

I'm still getting the feeling that you don't have a real appreciation how difficult it will be to make the 254 lbs weight limit. I started flying ultralights with a Quicksilver MX and even that was above the legal weight. Every UL that I've owned has been over the legal weight.
 
2
Top