Hobbycraft 1/72 F-89A/B Scorpion

[SkyPainter303]

Since my bomber build is going so well, I thought I'd jump over here and join the Cold War build. I knew I wanted to build an aircraft and I wanted it to be something obscure. So, I chose an aircraft that saw no combat and had a short lifespan. The kit is also from a manufacturer many choose to avoid.

Here are the shots of my new-to-me, Hobbycraft F-89 Scorpion.


P1020172 by Michael Keogh, on Flickr


P1020174 by Michael Keogh, on Flickr


P1020175 by Michael Keogh, on Flickr


P1020176 by Michael Keogh, on Flickr


P1020177 by Michael Keogh, on Flickr


P1020178 by Michael Keogh, on Flickr


P1020179 by Michael Keogh, on Flickr


P1020180 by Michael Keogh, on Flickr


P1020181 by Michael Keogh, on Flickr

[SkyPainter303]

Historical Summary

The Northrop F-89 Scorpion was born from an Army Air Technical Service Command requirement for a next generation night fighter. The requirement was for an all-weather aircraft of conventional, propeller driven design. The top speed needed to be 525 mph at 35,000 feet or 550 mph at sea level with a time to climb of 35,000 feet in 12 minutes. The desired range was 600 miles and it had to able to fire aerial rockets.

The design Northrop put forth was jet propelled. A propeller driven design simply could not meet the speed requirements. Northrop was competing with Bell, Consolidated-Vultee, Curtiss, Douglas, and Goodyear. Nortrop won the contract to build two prototype XP-89 on 3-May-1946. The XP-89 design had thin, straight wings with split ailerons, called decelerons that worked either as regular ailerons, as flaps, or as speed brakes.

The XP-89 was powered by two Allison designed, General Electric J35-GE-3 engines mounted under the fuselage. The original plan for armament was four 20mm cannons mounted in a nose turret. Ultimately, the F-89 was armed with six, conventional Mk24 20mm cannons. In June 1948, the aircraft designation was changed from P for pursuit to F for fighter as per the new Air Force system of aircraft designation.

In June of 1949, Northrop was awarded a 48 million dollar contract to build 48 F-89A aircraft and supply spare parts, tools, and ground equipment. The F-89A was the first version to be armed with the six 20mm cannons. There were problems in the beginning when the XF-89 prototype crashed on 22-FEB-1950. The horizontal stabilizer experienced a flutter. The solution was to add six, external mass balance horns to the elevators. This was just one change of many including new, more powerful J35-A-21 engines.

The first production F-89 was accepted by the Air Force on 28-SEP-1950. Only 18 F-89A were produced. Because there were so many changes to improve the aircraft, the remaining planes in the batch were redesignated F-89Bs or F-89Cs. Only a small number were actually provided to operational units (which happened even after the F-89B entered service.

The F-89B was externally identical to the F-89A. The B model had a Lear F-5 autopilot, an ILS system and a Sperry Zero Reader that combined the artificial horizon, directional gyro, magnetic compass, and altimeter. The F-89B received yet another more powerful engine package (J-35-A-21A turbojets). The first F-89B was delivered to the 84th Fighter Interceptor Squadron, 78th Fighter Interceptor Group at Hamilton AFB, California in February of 1951


F89 Scorpion-8 by Michael Keogh, on Flickr


F89 Scorpion-9 by Michael Keogh, on Flickr


F89 Scorpion-11 by Michael Keogh, on Flickr


Northrop F-89 Scorpion by Michael Keogh, on Flickr
XP-89


Untitled by Michael Keogh, on Flickr


f89-2 by Michael Keogh, on Flickr

[SkyPainter303]

Tonight, I started my F-89 build. The Hobby Craft instructions are a bit vague so I downloaded the instructions for the Revell F-89 so I could have something to compare to. The Revell instructions also have complete color call outs.

My first problem with this build was the broken rear seat on the sprue.


P1020188 by Michael Keogh, on Flickr



Here is the assembled cockpit which needs to be primed and painted.


P1020189 by Michael Keogh, on Flickr


P1020190 by Michael Keogh, on Flickr



I am not sure the rear seat is installed correctly because there are no positive locating pins. But, I glued it in what seemed like the most logical position. The seats still looks to be reclined more than it should be.

[warpedcrisis]

Nice start there

[smokeriderdon]

Very cool subject. Is it just me, or is that nose cone much too pointy?

[SkyPainter303]

Very cool subject. Is it just me, or is that nose cone much too pointy?

The tip might be too pointy and the overall shape might not be long enough.

[smokeriderdon]

Yeah, that's what I was thinking.

[SkyPainter303]

This Hobby Crap kit is a real challenge. I got the cockpit primed and painted. It was primed in black Stynylrez and painted with a mixure of Vallejo, Model Master acrylic and Tamiya.


P1050083 by Michael Keogh, on Flickr



While putting the fuselage together, the front instrument panel fell out and so did the pilot seat. I got the panel back in, and will put the seat back in later. The kit instructions are vague and fit is poor. The parts that have the fan blades needed to be trimmed in order to fit the fuselage bottom. I also foresee some problems with the exhaust nozzles and exhaust shields. We shall what happens back there. Installing the bottom required liberal amounts of Testors Liquid Cement and super glue. I got the part wedged in there and clamped by my hand for five minutes each section. Upcoming will be much filling and sanding to make it right.


P1050088 by Michael Keogh, on Flickr


P1050090 by Michael Keogh, on Flickr


P1050091 by Michael Keogh, on Flickr


P1050094 by Michael Keogh, on Flickr


P1050095 by Michael Keogh, on Flickr

[pourquoi61]

A very nice choice and great work so far.

[SkyPainter303]

Like most Hobbycraft kits, this one requires some filler. I got the fuselage bottom installed along with the exhaust heat shields, and the air intakes. Next up will be the wings and tail surfaces.


P1050102 by Michael Keogh, on Flickr


P1050104 by Michael Keogh, on Flickr


P1050103 by Michael Keogh, on Flickr

[NorthernModeller]

Looks to be a nice little build. Filler here and there but that is part of the process looking good mate

[SkyPainter303]

The construction is wrapping up. For nose weight, I used some large fishing weights and some Hobby Lobby Tacky.


P1050105 by Michael Keogh, on Flickr


P1050106 by Michael Keogh, on Flickr




The early model Scorpions didn't have the upper air scoops on the fuselage, so the mounting points needed to be filed off.


P1050107 by Michael Keogh, on Flickr




The rest of the assembly is coming together well only needing small amounts of filler. I still need to add filler to the wing tank mounts.


P1050109 by Michael Keogh, on Flickr


P1050110 by Michael Keogh, on Flickr


P1050111 by Michael Keogh, on Flickr




As I was masking the canopy, I realized that the part is all wrong. This is a later model canopy, the early ones don't have the center frames. The shape also appears to be wrong. The windscreen is also missing some extra bracing.


P1050108 by Michael Keogh, on Flickr


Squadron Signal - Aviation - In Action - 1104 - F89 Scorpion-10 by Michael Keogh, on Flickr

[SkyPainter303]

I installed canopy, but only after cutting off the bottom of the seats and trimming a corner off the rear instrument panel.


P1050112 by Michael Keogh, on Flickr



The horizontal stabilizer needed a little filler. I also glued on the twelve mass balancers.


P1050113 by Michael Keogh, on Flickr



At this point the model was ready for primer. I chose to go a simple route this time using Model Master Gray Lacquer Primer in a rattle can. It went on great, yet a little thicker than using an airbrush primer.


P1050116 by Michael Keogh, on Flickr



After the primer coat was dry (two hours according to the can instructions), I airbrushed on some Model Master Enamel Flat Aluminum.


P1050118 by Michael Keogh, on Flickr


P1050119 by Michael Keogh, on Flickr



This kit gets some pretty horrible marks from builders on the internet, but despite this I am pleased with the outcome.

[SkyPainter303]

Next up is the landing gear. Like the rest of the model I primed in Model Master Lacquer.


P1050121 by Michael Keogh, on Flickr

[NorthernModeller]

Landing gear is my least favourite thing on any aircraft looking good mate

[pourquoi61]

She is looking good, so keep up the good work.
The Hawk 75 is a good build and no filler.

[SkyPainter303]

I've been waiting for the Model Master Aluminum enamel paint to cure before I put on some clear in preparation for decaling. The oils in my skin seems to reactivate the paint when I handle it. Either, that or the paint is still soft. It has been days since I painted this model.

[pourquoi61]

Yes I have found that out to my expense after handling models with out gloves on.
My she is looking good.

[smokeriderdon]

I've been waiting for the Model Master Aluminum enamel paint to cure before I put on some clear in preparation for decaling. The oils in my skin seems to reactivate the paint when I handle it. Either, that or the paint is still soft. It has been days since I painted this model.

It could also be humidity. I would definitely wear some rubber gloves.

[SkyPainter303]

This one is almost done. I did some remaining detail painting, placed the decals, and added the landing gear. Sadly, I lost one of the front gear doors. Oddly, the decals did not match those in the diagram. The actual decals were not the same size; the wing decals were too small and the fuselage markings were too big. The national insignia are all the same size.


P1050130 by Michael Keogh, on Flickr


P1050131 by Michael Keogh, on Flickr


P1050132 by Michael Keogh, on Flickr


P1050133 by Michael Keogh, on Flickr


P1050134 by Michael Keogh, on Flickr

[pourquoi61]

Will you make the front wheel doors?

[Maverick231]

Looking good mate
Always liked this aircraft, especially with the giant rocket pods that were fitted later in the jets life.