Great People, Great Products & Great SERVICE!

NOTE: We are having a new phone system (with expanded lines,etc..) installed today
Tuesday, April 27, so if you have difficulty getting hold of us please be patient - it'll be worth the wait!


STEINAIR HOME

!The 4th Younkin Mullicoupe!

This is the page where I'll try to slowly update the project for the 4th Younkin Mullicoupe going together in my shop.  For now, enjoy some pictures.

What is a Mullicoupe? - well to put it simply it's a cross of the Mr.Mulligan (Howard DGA6) and a Clipwing Monocoupe 110.
 The plane is the brainchild of well known aircraft legend Jim Younkin (who's credits also include a score of Staggerwings, the Travelair Mystery Ship, Mr.Mulligan, etc..)
This is a fairly rare bird, with only 3 other examples flying.  This is the "4th" (and last) one, and I'm extremely proud to have been given the opportunity to get it in the air.!

Approximate Spec's:

                Engine: Pratt & Whitney R-985 @ 450+ horsepower.
Propeller: Hamilton Standard 2D30, 100+ inches in diameter.
Wingspan: 29'
Length:    22'
Height: 8'
Empty Weight: 2200 lbs
Gross Weight: 3600 lbs
Fuel Capacity: 140 gallons
Seats: 2
Cruise Speed: 200kts +

Pictures of other Mullicoupes and planes.
(There aren't many as there were only 3 other Mullicoupes ever built)!

Note: These pics are not all mine and were gleaned from many places including the internet.  If one of these pics is yours, please let me know so I can give you credit)!

Red Lerille's
Mullicoupe

Jim Younkins Mullicoupe.

Mark flying the Black Mullicoupe in Formation with Jim Younkins Red coupe.  Picture by Stein.


Bud Dake's plane now owned by Mark Holliday.

Jim standing by his DGA-6 "Mr.Mulligan" this year at the Antique fly-in, Blakesburg.

Panel of Bud/Mark's plane.

Younkins plane shown with Jim Wright (Hughes H-1 Racer).

Mark's coupe at parked at TruTrak.

Matt Younkin, Jim Younkin, Kyle/Amanda Franklin.

Matt Younkin, Jim Younkin and Doug Rozendaal.

Jim Younkin with his Mullicoupe.

The Howard DGA-6 built by Younkin.

Younkins Mystery Ship.

Mark Holliday strapping on the Mystery Ship with Matt Younkin giving instruction at Jim's 80th Bday bash.

Stein & Jim at Younkin's
80th B-day party shortly after flying Jim's coupe.

 

2009-10 Pics Below

Intersection fairing in progress.  Also gear leg wood fairing profiles taped in place.  Gives the gear a nice airfoil shape when covered in fabric.  The pieces will be welded together and then worked/sanded to make a complete fairing.

Strut to Wing intersection fairings.  Still some tweaking to do, but 90% done.

Here's the panel blank cut.  The rear attach angles are 3/4" square by .063", and I spend hours with the shrinker & stretcher to shape the swooping angles without using the old million little slices method! Contents of panel blanked out until I get it all done!
 
 

Gear/Fuselage
Intersection fairings in process.  LOTS of metal shaping in these complex fairings.

Another shot of the cowl test fit onto the plane. 

 
The cowl as built by Pat.  The bumps are HAND FORMED (bumped) - not stamped or welded in place.  The cowl is 2 piece, and the bumps were hand formed into each half of the cowl. Again a work of art.  You might recognize Pat's work on cowlings...a'la the Hughes H-1 Racer!
 

Top pic of the wing root fairing.

Close-up of the wing root fairing.

Wing root fairing rear veiw.

This is an extremely complex fairing (crafted by Todd), one piece top wraps all the way around the bottom, following the contour of the wing and also the fillet between the fuse and wing.  It's a work of art!

Look from the front left of the latest "visual progress". Engine hung!

It's on!

Engine hanging from hoist, getting ready to hang on the airframe.

Some of the 1" oil lines I've been building.  This is the turn from the belly feed lines up to the main oil tank.

Dishpan/Bootcowl progress.

More progress on the forward sheetmetal.

Dishpan/Bootcowl progress.
Hand Formed aluminum bootcowl/dishpan intersection pieces being joined to stainless pieces.

Dishpan being hand built from Stainless sheet.  Shrinker/Stretcher, English Wheel and other metal forming tools.

Close-up of one Stainless piece being formed in the English Wheel by Todd.

Dishpan going together.  Made from separate pieces of stainless that are then welded/formed together..

New Fuel Tank installed.  42 gallons. Welded by Todd S.

Another pic of the new fuel tank.

Todd Sutton forming another piece of the Dishpan on the English Wheel.

Wing Struts Done!
Wings mounted.

Wings on and mounted.

Master Craftsman Todd Sutton.  Todd worked on the original Mullicoupes, as well as MANY other aircraft.

Fuse with wings and completed struts. Although the wings appear to droop, they are slightly swept and have ZERO dihedral..

Wings on, Struts done, project now moving "forward"!

Lower main wing strut attach point.

Bottom main wing strut attach.

Working on Aileron and Rudder rigging..

Rudder pedals and brake master cylinders mounted.  We originally had floor mounted pedals, but then decided on overhead pedals....lots of work, but they turned out really nice.

Rudder pedal installation now almost finished!

Detail rudder pedals.
 

Front left wing upper wing strut attach

Trial fitting of the oilt tank and fuselage fuel tanks.

Close up of Oil tank (8.5 US Gallons) getting fitted to fuse behind baggage bulkhead.

Front Fuselage Tank (29 US Gallons).

Wing fitting, etc..

Rear view of fuel boost pump(s).

Underside of main and aux fuselage tanks.

Plumbing between boost pump (Airflow Performance) and filter.

Rear view of rudder pedals. Note the pedals rotate on needle roller bearings!

View from right rear underside of fuel tanks, boost pumps and selector valve.

Left Door Cutout. Fuel Tanks going in!

Fuel Boost Pump(s) plumbed up...yes, there is two...one will 'only' handle about 35 g.p.h.

More fuel boost pump plumbing with Andair fuel selector / valve.

Left Side Seat support, welded by master welder Todd S.

Cockpit looking aft at fuselage aux fuel tank and main oil tank.

Looking aft in fuselage at main and aux fule tanks. 

Looking in left door cutout. Tanks being test fit.
2008 Pics Below

Battery tray and servo mount from outboard.

Battery tran and servo mount from inboard.

Battery tray and servo mount from above.

Battery tray and servo mount from front.

Old battery used for test fitting.

View under the pitch servo/battery tray.

Another view of pitch servo mount being fabricated.

Right wing flap extended.

Profile view of wings.

With flaps retracted, the ENTIRE flap track/hinge hides inside the wing!

Outboard view of aileron and flap mounted on right wing. Wing is swept in both chord and span, as well as semi-elliptical in shape.

Wings are tried/true 23012 Airfoil.

R-985.  Bright shiny new engine for my Mullicoupe!

R-985
Waiting to be used!

Wings well along. Yes, they are wood!

Sitting in the shop, getting worked on SLOWLY!

Close up of left fuselage side.

Front of Fuselage.

Looking down the aft portion of the fuselage towared the tail.
 
     

 

 

 

 

SteinAir HOME

Copyright 2000-2008 SteinAir, Inc.
All Rights Reserved, all content is property of SteinAir Inc.
Homebuilding / Avionics Supplies, Projects & Resources

Hit Counter

The Mullicoupe Project

 GARMIN G900X EFIS