INTRO:
After winning 12 International Scale contests and winning the European Star Cup Championship for Scale models in 1994 + 1995 with my B-17 Flying Fortress 1/8th (1:8) (also in 1996 and 1999!), plans were hatched for a successor.
For sure it would be another WWII type, as this was my preference, but not another 4-engined one (like my Short Sunderland, 3,50m. span= 11½ feet, and the   B-17, span 4m.= 13 feet)), but a twin-engined fighter, just my choice was torpedoed by the Family. They thought the plane was too smooth! And they were right, because normally I build only scale models with character, as these are the ones which appeal to me! I suggested that they have a look for a type in a book "Aircaft of W.W. 2", and that I did regret (but not for long!), because there unanimous choice was the twin engined P-61B Black Widow! (scale 1/6,6th. 1:6,6 = span 3,10m=10feet).
That was the last one that came into my mind, as it is a very complicated aircraft! A difficult fuselage shape, as well the middle fuselage as the twin-booms, slightly gull -wings, limited ailerons and large spoilerons (large vented panels, moving up into the air from the rear upper wing surface), flaps like barn doors as well on the inner –wing as on the outer-wing, and last but not least, a tri- gear of which when the the gear is down, the mainwheel-welldoors has to be closed again, except one little piece (B-type). In addition, the whole plane is black!!
I had to think about this a little bit, with own drawing at least again a 3-year project! (existing plans were to small, or not accurate enough and their construction-methods are too heavy, with too much scale compromise, besides I always produce my own plans!).
So again from own plan, but first I had to collect sufficient documentation and for a general impression; a small plastic kit (1:48).
 

Prototype:
The P-61 Black Widow Nightfighter, was not only the biggest (span 66 feet= 20,12m), heaviest (32000 p=15.000kg) and most powerful fighter of the whole war (2 double-banked radial 9-cilinder engine Pratt & Whitney R-2800-65 engines at 2000 hp each) and very fast (370 mph=600 kmh), but also the only nightfighter so designed! Besides it was heavily armed with 4x 20mm cannons in the belly, and 4x 0,50 calibre machine guns in the upper turret, and had 3 crew-members!
The plane was in design his time far ahead, with a modern wing-foil, spoilerons and Zap-flaps.
It is not a fighter in the proper sense of the word, but a real   P= Persuiter for interception and destruction of hostile aircraft in flight during periods of darkness or under conditions of poor visibility!
When the model was almost finished, I obtained a P-61 Pilot Manual, and in it were flight restrictions, that when the plane was fully armed and had drop-tanks or –bombs, aerobatics were prohibited, and in all other cases just a slow roll– fast ½ roll– inside loop– chandelle– wing-over were permitted. But certainly never, outside loop– inverted flight– snap roll–spin– vertical reversals (and this was just I build the model for !!). So, some manoeuvres were also prohibited on contests, but not on Shows!!
Although the first plans were from 1940, the P-61 came, (owing to a long and complicated preparation of his radar-equipment), just in 1944 in service, almost on the end of the war. The plane did not fly so much over Europe, was still brought in action during the invasion in Normandy, however almost not as a Nightfighter, more for ground-attacks. They were very effective during the Battle of the Bulge (Ardennes, Belgium), scoring 7 aircraft kills in addition to destroying large amounts of rolling Stock and a number of locomotives.
In the pacific however she was put in action against the Japanese and mainly for that she was designed for : Nightfighting!
There were built in 3 main versions over 700 P-61’s. (P-61A: 213, P6-1B: 450, P61-C: 41). I have built the P-61B, because the nose is a little bit longer then the A-type, and the P-61C was delivered just in July 1945, to late for action, these were mainly used for tests and special missions.
In the whole world there are only two P-61’s intact. A P-61C in the Air Force Museum, Ohio USA, the other a P-61B, is strangely enough in the Institute of Aeronautical of Engineering in Peking, China. (the Communist troops have confiscated the last P-61,which should have flown home, in 1947, and refused to give it back!). Besides, neither planes flies anymore.
The remains of three P-61’s were found in New Guinea some years ago, one of them, a P-61B (the other two are P-61A’s) was shipped to the USA and is under restoration in the Mid Atlantic Air Museum in Pennsylvania, but I could not wait for that!

Documentation:
In view of the last above, it was not much help for me building a P-61B, so I had to document with reference books on the P-61, which I ordered from the USA, UK and Czech Rep. The expensive and thick books were very common and the cheaper thin ones were the most helpful, specially the Czech one and the Osprey publication. (both have excellent side- views, colour drawings, photos and details).

The imitated Prototype:
The more I was researching into the type of aircraft, the more I became interested in the construction and the complexity of the whole thing, and I decided not to avoid any problem or difficulty!
My choice was then finally the Lady in the dark! A P-61B from the 548 Night Fighter Squadron, based in the Pacific, which did the last kill of an enemy plane (Japanese) in WWII. Especially with its beautiful Nose-Art of this plane, and the extra red on the whole black plane, which is rare for a P-61! The pilot was Solie Solomon (he had changed his name in Lee Kendall after the war) and I had 15 years contact with him, untill he passed away March 2nd 2018 at the age of 98 years old.
 

The Engines:
I was very Satisfied with the 4x Laser 70 in my 4m. span B-17 Flying Fortress (Scale 1:8, weight 19,3 kg). So again I chose 4-stroke Laser Engines: Either the 200 V-twin (32cc) or the 150 single (25cc), so in Oct. ’95, I contacted Neil Tidey of Laser Engines. He had very good news, they were developing a new engine, the Laser 240 V-twin (40cc) with the same dimensions and weight of the 200 V-twin (32cc, 1160 gr.) and almost the power of the 300 V-twin (50cc, 1710 gr, ± 4 hp)! That suited me very well, now I could build the desired span of 3m. It became scale 1: 6,6 (span 3,10m =10 feet), the engines should fit very nicely in the cowls. The weight would stay (according to my own calculated method) below the max. of 20 kg. With this combination the model was allowed to weight 20 kg for flying Scale! (the eventual weight  later was 18,5kg!) The prototypes of these engines should be tested for 2 years, but then I would get the first 2 engines (were delivered Aug. 1997!).
 

Plan of the P61B (Scale 1:6,6 and span 3,10m)
Again the plan was drawn by myself (starting Sept. ’96), completely worked out, 99,90 % scale and nothing was left to a mischance. Everything, down to the last detail, was well considered and put on paper (old-fashioned isn’t it!), and the construction was kept as light as possible. Only the ribs were drawn with the computer, because the wing is tapered, and it has an airfoil changing towards the tip! (35mm slides were made from the more side-views and projected until the right scale, traced on transparent paper and afterwards the construction was drawn in, sections were drawn and also all the formers, etc.!). The plan was ready in Dec ’96 after 300 hours work!
 

The Retracts:
The tricycle Retracts again I had built myself in the spring of the same year (electric via a screw-spindle and micro-switches, but the gear I changed it in 2000), this in connection with the drawing, otherwise there would come problems during building!
 

The Fuselage:
January ’97. It took one month sawing with the Dremel, to produce all the parts for the model. The fuselage was built in 2 phases, just like with all my scale models: an underside section and an upperside section. The under-section has a complicated fuselage shape (also, because of the 4 build in and forward firing 20mm cannons) and was built up side down. Therefore the formers were drawn as split parts with a flat edge, and these were secured on the building board, some of them are from ply, a few are liteply, but the most are from balsaply (very light). From the start, the nosegear bearers and the 2mm plywood strengthener strips for these, were built in and the nosegear was mounted on them for a correct fitting and angle! Then all the formers were connected with balsa stringers, some of them were spruce, and the airframe was planked as far as possible.
When the glue was dry (mainly clear PUR. construction glue), the fuselage halve was turned upright, supported by foam blocks. Now the upper section could be build on, with provision for the wingjoiners (35mm dural tube in front, and 20mm at the rear, in GRP guide tubes). Wing and tailplane fillets are built in on the fuselage, and the flowing lines for them were achieved in the relevant formers.
Now the fuselage top could be planked and the whole cockpit hood made removable (as with all my large models, and the nosegear controls are very accessible). The hood has an extended floor, which fits into the fuselage to just above the retracted nose-wheel, this for a scale cocpit interior, and the two crew members (pilot and the gunner on a higher step behind him), the third crew member (gunner/radio operator) sits in a separate Plexiglass cabin at the rear. The fuselage contains only 3 servos: 1x control-linkage to the nosegear-wheel, 2x Servoswitches for electric Retracts and for Landinglight, and 2 batteries, one for each of them.
 

The twin Booms and Stabilizer:
The booms were even more difficult as there were many problems to solve; Booms are tapered from round nacelles at the front, to an oval section at the rear, the engine installation, maingear with 3-part gear-welldoors, to built the innerwing with flaps on to the boom, a removable rear-end with fins and rudder, disconnection of the stabilizer and inner linkage of the single elevator, installation of the numerous servos + linkages (throttle, flap, gear-doors, elevator, rudder and all as far as possible to the front), a chamber for the receiver + batteries, etc., this all twice.
I have kept the formers for the booms in one piece and lowered them down into slots in a building jig for each half. They were fixed with the spruce stringers (in cuts of the formers) over the building board! I also built in the main-gear bearers and the 2mm plywood strengtheners, for them are extended forwards up to the firewall. Also the provisions for the boom-separation (flat springwires in brass tubes + 4x M4 socket bolts, which are connecting the dual formers), immediately behind the wing. The half then was planked and turned upright, supported in foam blocks.
Not much could be done to the front (over the innerwing area) at this stage, as this part had to be attached later on to the underside of the inner-wing and glued to it in one piece. But the rear-end of the separated boom, could be finished, the finconstruction and the rudder was build on in one piece, and the inner rudder linkage was built in. Also the difficult inner elevator linkage (no servos at the rear in connection with wrong weight) for the removable stabilizer between the two booms (brass tube on the elevator, sliding into a twisting brass tube with control horn and supported in Paxolin bearers in the fin).
Two servos (in left and right boom) for safety, but operating the single elevator, so they had to be powerful servos, but easy to move with the fingers when current dead, in case one fails: Graupner JR servos C4821 new types 8,8 kg
(is not possible with the 10 kg old types, these I used for the large outer-wing flaps). The servos are installed in front of the rear boom, next to the rudder servos, all closed loop system linkage and M 2,5 kwiklinks! After that, the upperside could be planked too and separated from the front boom half, by loosening the 4 M4 socket bolts and saw through, between the 2 dual formers and through the flat brass tubes. In this way it will fit accurately! The front piece was connected later on to the inner wing-construction.
The rudder now was separated from the fin and became a convex leading edge.

The Stabilizer (NACA 0010) was the easiest part of all! and is placed between the 2 booms. This part was also built on raised supports (12mm cheap plywood strips). The only provisions were the four 10mm carbon tubes for connecting with the booms (secured with metalscrews) and the brass tubes in the elevator for direct control. So now the Stabilizer is sliding into the tubes of the boom and the control for the rudder has been achieved!
But the project was stopped for a while after a serious car accident (on my way home from the Dortmund Model Exhibition in Germany, almost home, a car with 4 ‘wild youths’ travelling in it, wanted to cross lanes between me and a car driving in front, but they did not quite make it! Two men in hospital and my car was a total loss!).
I received neck- and back injuries, so building was restricted and no flying at all! Seven months later I was able to build again, but for 2 years I did not fly contests and started again in 1999, but at the end of the season I was for the 4^th time European Star Cup Champion for Scale models with my B-17 Flying Fortress, so my fingers were not out of practice anymore! The fuselage, the 2 booms and the stabilizer were ready in April 1998,  just 2 years after starting, building the retracts also counted.
These 3 parts + stabilizer could be assembled with help of the dural tube wingjoiners, a few ribs of the wing and some clamps, this for first impressions. Already now a mighty sight!
 

Wings:
These were built during the winter-months ’98 –’99, my flying performance was increasing, so I took a fancy to start building again!
The wings have an own mix NACA profile 2414 / 2314 on the innerwing, and than further on, in the outerwing, progressing to NACA 0014 profile section at the tip. So an aerodynamic wash-out has been build in (a geometric wash-out with just twisting up ribs with the same profile, and so changing the chord incidence angle slowly, always gives drag!).
Wings I always build on raised supports (strips of 12mm cheap plywood), it allows building on later the nacelle construction. The slightly gull-V, the wash-out, the dihedral were already build in these supports (matter of drawing and calculating !).Because of the large wing chord I use 3 supports: under the main spar, rear spar, and ribends.
On these, with sellotape between it, the lower spars were pinned, then the ribs could be glued on, the upper spars and also the leading edge. (The rootrib at an right angle to the building board and all other ribs with an right angle to the mainspar support!). The provisions for the joiners (dural tubes in one long piece) for wing-fuselage were made and, so also for the fixed joiner for innerwing-outerwing. (later on secured with parkers straight through woodblocks in the wing and woodpieces in the tubes). The tip-ailerons (on the P61 more like trim-tabs, so small! For the plane is mainly flying with his spoilerons!) and flaps are build in with the wings, provided with half notched leading strips. The ailerons were provided, just like rudder and elevator, with pin hinges and through them a long 1,5mm pianowire in a plastic tube. The flaps were provided with special flap hinges, recessed into the undersurface, there is a gap between wing undersurface and flaps when these are lowered, giving so more lift and less drag!
After the open wing construction from left and right wing were ready (build on the same supports, but mirrored) in the supports were sawn out to make room for the front piece of boom with nacelles. Now finally this piece could be shoved into the undersurface of the innerwing section, first checked on incidence angle and levelled with bolted on temporary the rearboom end, then after this, final glued on and the rear end was removed again! Now also the still open inner- and outerwing could be separated from each other, for it was easier to make the necessary provisions for servos: inner- and outerwing flap, throttle, bomb/ droptank release pylons, tipaileron, spoileron, gear welldoors: in each wing 8 servos, total 16 servos just only in the wings!

The spoilerons are laminated, in a halfround and tapered moulding, of 3 sheets 0,4 ply and between them carboncloth + epoxy. They are hinged, almost at the rear, on the upperside and inside the outerwing, on a long 3mm pianowire in a plastic tube, so it can turn out of the wing (therefore in the ribs are sawed segment shaped slots), and is eccentrically controlled direct from a servo, turning up simultaneous with the small tipaileron on the same side. On the other wing the tipaileron is going down of course, but the spoileron remains almost unmoved inside the wing (on account of the eccentric control-linkage).
The ailerons, spoilerons and flaps are controlled with M2,5 rods, kwiklinks and bollinks, but the throttle by a sullivan pushrod. A tank space was created, on each side for 2 tanks 350cc (each cylinder of the V-twin Laser 240 with double carburettor has his own tank!), so also on each side an equipment-space for a receiver + batteries (on each side 1 receiver + 2 batteries, one for the receiver and one for extern power support for in- and outside flapservo, tipaileronservo, spoileronservo). After all satisfied provisions, both wings (inner- and outersection joined) could be planked. First the undersurface and than replaced on the supports and weighted down, this ensures the retention of a true straight wing. The same procedure was followed for the uppersurface, then the nacelles could be planked also. Planked flaps and aillerons were cut out and convex leading edges glued to them. Now everything was constructed and details could be made or placed.
 

Cowlings, Upperturret,Gear-welldoorblisters, Cone and Cockpit:
For all these parts I had to make the mouldings and plugs of ply and balsa filling blocks. The Cowlings (Ø 210mm), the Nose-cowl of the fuselage (contained the radar- equipment), the Upper-turret, wing-pylons and the main gear-well door-blisters I formed from GRP with help of a big balloon (blown up) and pushed over the mouldings.
The canopy-hood, the rear canopy and rear cone I formed, with plugs, from 1mm clear Butyrate plastic in the kitchen stove. The canopies were glued over a wooden frame (for scale looking the inside was already detailed, and so on), the outside was provided with a frame of aluminium tape-strips, which were cogwheeled before for a rivet effect!
The cowlings were applied with a 9- cylinder radial dummy engine.
 

Finishing:
Now I can start finishing the model;
After a final sanding, everything was covered with a lightweight Japan tissue (paper), 12 gram per square meter, and one coat of clear shrinking dope, and light sanded very carefully. Then scale panels and so on were scratched- in, than two more coats of clear shrinking dope and light sanded. A wash-primer was sprayed on and wet sanded, rivets were applied with PVA glue from a syringe. Finally the model was sprayed in the authentic scale colour (silk-glossy black 2 component acrylic), then a little bit weathered etc, was added. Markings and codes were sprayed on, the nose-art was hand painted and the final details were applied. It was almost half Mai 2000 and the model was finished!! Almost ready for his first European Star Cup contest, after test-flying of course.
 

Radio Installation:
At last my Graupner JR- MC24 (SPCM) radio equipment was installed and I did need all 10 channels. Total 27 servos!! (less was not possible, as it is a complicated model), 2x SMC20 receivers (I always fly my large scale models with 2 receivers: 1x for the right hand side and 1x for the left side!), 2 electronic switches, 6x batteries 1700 mAh (2x2=4 batteries for 2x Power Management System PMS-plus of Engel Modellbau, Germany. In 2012 the Recievers were changed for Graupner GR-24 Hott 2,4 Ghz). The 5^th and 6^th battery is in the nose of the fuselage and is for the electric retracts and retractable landinglights, these batteries also helped balance the model! (no lead at all!)

Fuselage servos:1x retract servos-witch + 1x landinglights servo-switch + 1x nosewheel linkage control  = 3 servos
Boomservos:2x elevator + 2x rudder = 4 servos

Wingservos:  Innerwings :2x innerflaps+ 2x throttles+ 2x pylon Bombdrop+ 4 main gear-well doors(2x2 =4, 180⁰ servos)= 10 servos
                         Outerwings:2x outerflaps+ 2x spoilerons+ 2x tip ailerons+ 2x pylon droptanks+ 2x retractable landinglights = 10 servos

See also chapter Technical Solutions for my Large Scale Models.

Test Flights:
The first was Saturday 3 June 2000 at 11.30h on a Dutch Air Force base nearby. Did not have faintest notion how these spoilerons would react in the turns during flight, with the super small tipaileron combination! So I needed extra space to allow for this!
The model was assembled and the tanks fuelled (The engines were tested and run in, during the 1999 season on a 2m. span Sukhoi 26 and they proved to be very reliable, so I had faith in them!). Everything was finally checked again! The engines were started, just a short taxi trial and the big moment was now there!
Will she fly or not? Is the centre of gravity correct, are the incidences correct? Slowly the throttle control was opened, rolling and picking up speed, a little touch of up elevator and literal for my son Jorn and other nosey ones, the model came air-born in a nice slow climb. At once I had a very good feeling and the first and tense turn was started.
The spoilerons in combination with small tipailerons, responded superbly and in a flowing movement the model made its first turn! First gaining some height, flying a circuit on ¾ Throttle, then the retracts up.
With enough height I checked how slow she could fly, the result was superb! The model did not give away anything and importantly did not stall, but just nodded its nose forwards to make speed again! So I knew that the landing could be made with confidence. But now for the first just real tests! Full throttle and let’s roll, the spoilerons reacted very well for this. The 4 stroke, 40cc V-twin laser 240’s were running outstandingly and what a sound they made. The deep beat of these engines is quite thrilling! Neil Tidey did again a fine achievement. But at once it also showed that the props were the wrong ones! Pitch too low, for between ¾ and full throttle the speed did not increase and the props started to howl. So I decided not to fly a loop until I had fitted different props!
After 10 minutes test-flying a circuit was made, throttle back, landing gear down , flaps 30⁰ down, and the model made a slow and steady approach, followed by a smooth touch down on his main wheels and slowly also onto the nosewheel. Test-flight successful!! A resounding applause was my award!

The second testflight was a week later, now with different props, on the airfield of my homeclub M.F.C. Delta Oss.
But things did not going well, the left maingear leg was turned 90⁰ immediately after airborne (tightness was released), therefore blocked against the wheel-well. I decided to make an emergency landing with the gear retracted instead of lowered and one wheel diagonal!! But the P-61 can approach very slowly with full flaps, so that the damage was restricted to a few small cracks in the belly. A little Zap –glue and soon it was fixed!
The following day, the third flight. Everything was going superbly, with perfect large loops, successful stall-turns, very nice 45⁰ Wing-overs and slow- rolls. The prototype was prohibited to fly most of them, so also for the model on contests, what a pity!
 

Flying Contests & Meetings:
It was and is enjoying, flying this Model, also so realistic and majestic! Made many flights and did win over 10 International Scale Contests all over Europe.
In 2003 I flew my very last Contest  and that was with the B-17, than I stopped competing Contests (for the time being)From 2004 till up to2016, I participated only in Warbird & Scale Meetings in the Netherlands, Germany and England

In 2010,
I have updated my plan in 2010, made some changes, for example more details.
Now I am selling these updated plans myself, not via others anymore ! Others are selling my old plans, mostly illegal !

In 2017, I participated for the first time since 14 years again in a Scale contest.
In the National Championships Scale, got with the P-61 the 2nd Place in the Final Result, not bad after 14 years unpractised.!