Revell-Monogram 1/48 F-89C Scorpion

A neighbor and friend who I have grown to like and respect over the years owns a wonderful restaurant. It is in the former hotel, the oldest building in town, which his family restored. The restaurant, known as The Dog Bar is well known for the steaks. Ron, like me, is an Air Force vet and was in the same career field. In the bar/waiting area he has a wall decorated with memorabilia from his time in the Air Force. They include many photos of the F-89C in the livery of the 74^th and 57^th FIS. I decided to surprise him with the 1/48 scale Revell-Monogram F-89C, built with the markings of the 57^th.

HISTORY

The history of the F-89 has been covered in detail in other reviews, most notably Roger Jackson’s. To those who are unfamiliar with the F-89, Roger’s review is an excellent starting point. I will cover briefly the service of the F-89C and the maintenance troops perspective. Ron has kindly agreed to talk to me at length about it.

The F89C had short and troubled service life. It was considered to be the first all-up operational model of the F-89. They were an improvement over the B model, but quickly replaced in line units by the much more potent D model. The C models were then sent to National Guard units.

The F-89C had uprated Allison J-35 engines. The allowable gross weight climbed to 42,827 pounds. Also, the elevators incorporated internal mass balances instead of the external balances on the B model and in May 1950 the Air Force placed an initial order for 63 F-89Cs.

The F-89C first flew in September 1951 and flight-testing ran concurrently with production. Northrop Grumman states that the production run amounted to 163 aircraft. Other sources have given the figure at 172. The first of the Cs reached the line units in February 1952, with the 176^th FIS in Wisconsin being the first unit to re-equip with new model. The 176^th received their first C on 8 February 1952. Over the next year and a half the 27th, 57^th, 174^th also flew the C model.

Just 23 days after receiving the planes, the 176^th FIS suffered a loss when one of their F-89Cs shed a wing and spun in, killing the crew. Speed and G load restrictions were immediately imposed by the Air force. It was felt that the flight crew had pushed their new equipment too far. On June 18, 1952 another F-89C, this time from the 74^th FIS was lost, just three days after the squadron was declared operational. Again the crew of two failed to survive. The loss was due to the same cause, and even stricter limits were imposed. Three more Scorpions were lost due to wing collapse in 24 days, between August 30 and September 22 1952. However the crew of the F-89 from the 74^th FIS lost on September 22 was able to eject safely and vital new evidence surfaced. The F-89 fleet was grounded and investigation and solution proceeded hand in hand.

The root of the problem was multifaceted. Part of it was the fact that the aircraft was operating in an envelope where many of the factors were unknown. Another part was that new materials were being used and the testing process turned out to be tragically inadequate. The wings were being ripped off at the fuselage attach point. In an effort to make the broad, thin wing as light as possible, new alloys were being used. The wing attach point was made of an aluminum alloy, T75ST. The alloy promised high strength and light weight. Due to limitations at the Northrop facility during structural testing, the physical testing could be done only to 60% of the design stress. Enough information was derived from the testing that engineers felt that the rest of the range could be mathematically extrapolated from the initial results. After the losses, a new testing program was instituted. The program was moved to a facility that could adequately subject the plane to a full range of wind tunnel and static testing. When testing was resumed, it was found that the new alloy was failing catastrophically. The new alloy was extremely susceptible to fatigue at the high end of the testing loads. Also any machining errors such as nicks or gouges induced fast spreading cracks and centers of fatigue. This “notching” fatigue surfaced in other aircraft that also used the new alloy, such as the B-45 Tornado.

It was found that the wing wasn’t just failing. The thin wing under certain flight loads would twist and flutter before the pilot could realize what was occurring. Because the control system was hydraulically powered with no “feel” or feedback there was virtually no warning to the pilot. At the design limits, to which combat aircraft are normally flown, the large wing would behave in a springlike fashion, rapidly oscillating and twisting. This flutter occurred in a way that it interacted with the airflow that would increase the wing oscillation. Once it began it would rapidly increase in rate and violence. This in turn would exceed the strength of the attach fitting and the wing would separate at the root.

The entire fleet was remanufactured using a high strength steel attachment fitting, and the wing structure was beefed up and strengthened. Fins where also added to the aft portion of the tip tanks to use aerodynamic compensation to help counteract the tendency for the wing to oscillate. After the fixes the F-89 went on to achieve an admirable safety record.

The F-89C In Service

Mr. Ron Schenne, the recipient of the model graciously allowed me interview him about his experiences with the F-89C. He was in service in the USAF from 1950 to 1954. Ron was an armament technician who also worked on the F-86 and F-94.

What was it like to work on the F-89? Ron said that in his opinion the large gunbay doors made the F-89 the most accessible of the three. However, because the F-89 carried 20mm and the others .50 caliber, the weight of the belted ammunition made it a little more difficult to work on. Also, the F-89 had bins to collect the spent casing and links. These were to prevent engine ingestion and also the help maintain the center of gravity as the round were expended. As the lighter spent casings were ejected from the guns they were passed backwards to the bins, which were closer to the aircraft CG. This placement helped preserve the weight and balance. On the other aircraft the spent links and casings were ejected overboard. This meant one more step being added to rearming the aircraft.

The guns were easy to boresight and stayed in adjustment longer than the lighter machine guns. Because of the weight they were harder to remove and install but enjoyed excellent accessibility. Far easier than the F-94, where the guns had terrible access to the mounting bolts.

Another point that Ron made was that the radar operator’s seat was far more spacious and comfortable than that of the F-94. He stated that a man of average proportions would have to “scrunch” down to fit in the radar operator’s position in the F-94, while in the F-89 that position was large and roomy. He stated the flight crews seemed to appreciate the roominess.

THE KIT

The kit comprises 75 pieces, molded in silver-gray, the old standard issue plastic silver. There are four transparent pieces, the windshield, canopy, the radio compass and a tail stand, should one not add weight to the nose. The molding is crisp and for the most part flash free. The panel lines are raised, with recessed vents, scoops and intakes. The cannon bay doors have recessed outlines and recessed reveals around the moveable control surfaces. There are decals for two aircraft, one from the 57thFIS and one from the 74^th FIS. The instructions are exactly what we’ve come to expect in a Revell-Monogram kit.

CONSTRUCTION

Construction started with the research. This was the first major stumbling block. While there is some material out there covering the F-89, the F-89s never went to Korea, or engaged in combat, and as a consequence never achieved the fame of it’s some fighter brethren. On top of that, the early models had limited production runs and were overshadowed by the more spectacular later models. I went on line, checked through the library and posted a help message in a forum as well. I did not have the time to run down every source due to extraneous, outside deadlines to complete the construction. My research failed to obtain a single cockpit photo of the interior layout of any of the early Scorpions. I did find shots of the J models and there is a resin detail replacement cockpit for the J model as well.

I built the kit straight out of the box, correcting any discrepancies I encountered. These were minor and consisted of removing the rocket launching stubs, which were molded to the lower wing halves, filling the aft electronic bay cooling vents and air scoop mounting holes. The aft electronic bay intakes and vents were added with the advent of the D and later models. The C model also had the rocket launchers deleted. They were only found on A and B models.

I started by gluing the upper and lower wing halves together and setting them aside to dry. The slots for the aft cooling scoops as well as the vents were filled with putty and the fuselage halves were also glued at this time. I test fitted the wings and tail unit. I taped a large tapered lead-fishing sinker to nose to find the placement to offset the tail-heavy stance. This was then superglued into the nose where it fit snuggly. The tip tanks were also built. The tanks were two pieces, the top and bottom halves. These assemblies were set aside while I moved on to the next step.

I started construction of the ”office”. The office is composed of a cockpit tub, pilot’s control stick and radar operator’s stick, two instrument panels, the two seat assemblies and the transparent radio compass beacon. The seats are four piece affairs that compare nicely to photos I had. The pilot and radar operator had seats that had significant differences in their appearance, and R-M captured this. The seats were done well enough not to warrant wholesale replacement.

There were some differences between the cockpit tub and real item. The most significant differences were the right aft cockpit consoles. They are molded at an angle, while in reality they are vertical panels. This was probably done to be able to have molded detail on the panels, ease manufacturing, and lower costs by not having to add separate panels for that location. The resulting panels, after painting and dry brushing had a very “generic” look to them. If I had time and motivation, I would have added more detail, such as throttles and switches. However, this was going to end up as part of the décor’ of a restaurant where 99% of the clientele would not even look at it.

The instrument panels were nicely done, the pilot’s panel, particularly looked very good. The radar operator’s panel had a generic; this could fit any plane, look to it, without even a radarscope. Without good photos of the rear panel I was at a loss. I wasn’t sure whether the operator had the old style of two small scopes or the later style of one large scope. The outline of the panel looked appropriate though. Again, I had to realize that I could detail this thing to the nth degree and no one would see or notice. Any of the customers that would look at it would see a rear panel, but none of them would know how accurate or inaccurate it was. The sticks both appeared adequate, with molded buttons and/or triggers.

The photos I had showed the interior, as well as the inside of the canopy structure, seals and seats to be a medium gray that Model Master neutral gray fit perfectly. The instrument and side panels were all uniform flat black. These were painted using Model Master acrylic flat black. The dials were then inked in using an India ink drafting pen. A drop of thinned red was placed in the pilot’s radarscope. The instruments and panels were then dry brushed with neutral gray. The bottom of the radio compass was painted orange-red.

The seats were given a coat of neutral gray prior to assembly. The headrests were painted flat red and the belts painted light gray with Metalizer steel buckles. The ejection handles were painted flat yellow. The assembly of the entire office was straightforward with no problems. The fit was good and the final product was satisfactory.

While constructing the office, I was simultaneously cleaning up the wings and fuselage. The rocket stub launchers were cut off, all seams, the area of the launcher stubs, and any areas filled in were sanded with 300, 400, 600, and 1200 grit sandpaper, then polished with Brasso. When I had achieved a smooth enough finish, the panel lines were rescribed, and the assemblies set aside.

Once the office was completed, it was installed as per the kit instructions. The engine fronts and bulkhead were installed next. This piece has a definite up and down side to it. Careful test fitting was required to make sure it was aligned correctly. Now came one of the parts that were called out in both the reviews and by several friends as one of the trickier parts of the assembly process; attaching the fuselage bottom. This piece contains the nose gear well and mates along the engine centerlines. Dry fitting revealed that the alignment was off. I used a procedure of aligning and cementing one small section at a time. I worked from the rear to the front and this allowed the whole piece to be slowly pulled into alignment. The engine intakes were then added. The fit was a little off on these. They required minor applications of filler. The engine exhausts and deflector shields were left off until after painting. At this point all the remaining sanding and polishing was done using the same method described earlier.

Mating the wings to fuselage was done with care. The tabs on the wings appeared awfully small to support the weight of the wings. Also, this was a present to a non-modeler, so I wanted to make sure wing joints were strong enough to take any unintentional mishandling. I took Roger Jackson’s advice and installed a solid brass spar to anchor the wings. I checked carefully for a location that could pass cleanly through the fuselage and into the wing. Initially I chose the location of the main wing spar. That would pass behind and under the cockpit assembly. However when checking the wings, the main gear wells would interfere. I finally chose the aft spar at the flap hinge line. Matching holes were drilled in the wing butt wall and the fuselage. The brass rod was glued with CA adhesive into the fuselage. The wings were butt joined with a technique that I have developed to increase strength. The wings were slid over the spar and CA adhesive applied. A small gap was left at the wing fuselage joint. Tenax 7R was liberally applied to the butt join. The wing was then pushed firmly onto the fuselage, aligned and set aside to harden. The assemblies were now ready for painting.

CAMOUFLAGE & MARKINGS

The Scorpions used by the line units were natural metal finishes with various color trims. I wanted a bird from the 57^th FIS. The 57^th trimmed their birds with a vertical black stripe around the nose forward of the anti-glare panel and the lower portion of the tail was also black. The tip tanks were pained anti-glare flat black on the inside halves, while the outside was NMF with a vertical black stripe at the center of the tank. All the black markings had white stars superimposed on them.

To start the painting, the inside tanks halves were masked and painted flat black. The lower portion of the tail was painted gloss black. The elevator and upper tail had been left off. The upper tail was painted light gray. After adequate drying time the tail and inside halves of the tanks were masked and the entire aircraft sprayed with buffing Metalizer Aluminum Plate. The aircraft was polished using a soft cloth. The movable surfaces, the flaps, decelerons, and elevators were left unpolished to provide contrast. After polishing, the plane was given a light coat of Metalizer sealer. Now, different panels were masked off for painting in various shades of Metalizer colors. The leading edge panels on the wings and elevator, top and bottom, and the engine intakes were painted in chrome silver. The gun bay doors, aft half of the engine nacelles, the flaps and landing gears and wheels were painted with non-buffing steel. The exhaust nozzles and the exhaust deflector keel panel, aft of the engines and gun blast panels were done in burnt metal. A light coat of sealer was then applied and after drying the masking removed.

At this point, the tires were painted with Tamiya XF-63 German gray. The German gray is a more realistic dark gray of used tires, as opposed to the black, which just appears to me as unrealistic, I guess we all have our quirks. The wheel hubs were given a wash of black. The sliding portions of the landing gear oleos were done in chrome silver.

The aircraft was now ready for decals and final assembly.

The kit-supplied decals were for serial numbers 51777 from the 57^th and 51851 from 74^th FIS. I wanted to portray a bird from the 57^th, just not the one from the kit. The decals supplied with the kit for the 57^th markings were for either a flight or squadron leader, which carried a black vertical stripe with white stars on the fuselage, forward of the intakes. In addition, it sported white checkerboard pattern on the main gear doors, and a black diagonal stripe on the waist. The tail carried three stars in a triangle and the squadron badge. A large 77 was carried on the sides of the nose, forward of the stripe. The kit also included decals for the anti-glare panel, the prominent rescue and service information panels on the fuselage sides beneath the cockpit canopy, the no step warnings for the engine blow-in doors and the pilots egress step markings.

The aircraft I wanted to build for Ron carried the marks of the 57^th FIS. Roger Jackson had sent me a picture of one of the line birds, 51771. This aircraft, at least in the picture, displayed neither the badge on the tail, nor the large two-digit nose number. The outboard aft end of the tanks, aft of the squadron stripe was flat black, which meant a few minutes more painting. By combining the serial numbers, buzz numbers and tail markings from the kit-supplied decals I could reproduce 51771. The decals were applied using Microsolve and Microset method without problems.

CONCLUSIONS

I found the kit a pleasure to build. It takes up a large amount of shelf space, but provides an attractive model that actually looks like a Scorpion. There were far fewer modifications and filling and sanding than found in many other inexpensive kits. The kit took me one week, working under a deadline and presented no challenges that the average modeler cannot conquer. The criticisms are few and far between and have already been covered in detail, but to reiterate, they are, the rocket stub launchers and the aft electronic bay cooling scoops and vents.

ACKNOWLEDGEMENTS

I wish to thank Mr. Roger Jackson who not only was a valuable resource in his own right, but urged me to write this review and helped in all phases of the technical aspects. Susan Csaba, my better half, who encouraged me and helped with editing and preparation. Also, let’s not forget Scott Van Aken who made this all possible. Last but not least, I wish to thank Mr. Ron Schenne, who took the time to talk and answer the various questions about actually working on the F-89C.

REFERENCES

Gatlin, Wayne, Col. USAF; “Flying the F-89”; Air Classics, Volume14, Number 10, October, 1978

Trimble, Robert L., “Scorpion”, IBID

“F-89 Scorpion” www.military.cz/ undated

Kinzey, Bert, The F-89 Scorpion in Detail and Scale, Kalmbach Publishing; 1993

“The Official History of the F-89 Scorpion”; The Northup Grumman Corp Inc. undated

“The Troubled F-89C” ; www.ufx.org/kinross/ undated

Mr. Ronald Schenne; Personal communication, 2003

John Doerr

July 2003

KIT #	4825
PRICE:	$16.00 at Great Models
DECALS:	Two Aircraft
REVIEWER:	John Doerr
NOTES: