What needs to be fixed to make the HobbyBoss P-61 a true B

[oyoy5]

I have heard people say the kit is closer to an A model than a B. Does anyone out there make an aftermarket nose which I have heard is the main is. Any ideas would be appreciated, I appreciate it.

[Dave Williams]

Correct B nose here.

 

http://www.relishmodels.co.uk/relish-resins-1-32-p-61b-black-widow-corrected-nose.html

 

You'll also have to modify the main gear doors for a -B.

Edited July 16, 2013 by Dave Williams

[Steve Sobieralski]

I have been working on the Hobby Boss P-61 for the past month or so, and have become fairly familiar with the kit. I will be building two, an early A-1 and a late B. Currently I am working on the A-1.

 

As part of this process, and for my own curiosity, I have produced the following list of differences between the various sub-types of both the A and B models, and the modifications to the kit required to produce that particular type. I am not a P-61 “expert”, but over a period of years I have acquired most of the available references on the P-61 and I have used these, as well as information available on-line. I am sure that this list is neither complete nor without error and there are several areas where changes are mentioned in the literature, but with no descriptions or illustrations that I have been able to find. These include the original hydraulic actuation for the landing gear doors, early cockpit heating system, differences between the early and later radar units, wing landing light changes, and several others.

 

The steps below refer to the 1/32 HobbyBoss P-61B kit instructions. Because of the step-by-step nature of the list I am afraid it is a bit redundant in some areas.

 

P-61A-1

Step 2

If you delete the gun turret (see Step 21) I believe that you should also delete the gunner's and R/O's gun sights, parts W1-4, W6-7, WW12, W26 and W32. You may also consider deleting the gunner's seat altogether, although I have read that turretless P-61s sometimes carried an observer in the gunner's position as an extra pair of eyes.(Edit 9/14/2013)

 

Step3

Delete parts Z15, Z16 and fill the hole in part K35, which is the pyrotechnic locker and should not have an oxygen hose attached to it.

 

Step 4

Delete parts K2, K3 and J47. P-61As had a different heating system. The P-61 pilot’s manual states that the P-61A pilot’s seat was mounted on tracks to move fore and aft.

 

Step 9

Delete parts K8, K11 and Z1. P-61As had a different heating system.

 

Step 10

There should be an oxygen regulator and hose, similar to parts K25 and Z11, provided for the gunner.

 

Step 13

Delete parts L5, V9, X32, L20 and X34. I don't believe P-61As had any forward landing gear lights.

 

Step 14

Delete part L18 and replace with hydraulic struts. Mechanical actuation of the front gear doors was introduced on the P-61B.

 

Step 17

Parts H1 and H3, remove the forward part (8 scale inches) of the fuselage back to the front of the wheel bay. Delete part Z14, there should be an oxygen regulator and hose, similar to parts K25 and Z11, provided for the R/O.

 

Step 18

The radar in the P-61A was an earlier model than that in the P-61B. I don’t know which one the kit represents or what the visible differences were, if any.

 

Step 20

I believe that parts K30 and K31 should be deleted and the indentations on the fuselage sides that receive them should be filled. I have yet to find a photo of a P-61A that shows these air scoops fitted. Note that parts K39 and K41, or H16, N2 and N17, may be deleted if the turret is deleted in Step 21. (Edit 9/14/2013)

 

Step 21

Delete turret unless building one of first 37 A-1s.

 

Step 23

If not installing turret use blanking plate part RA2.

 

Step 28

Instead of using parts PA11 and PA18 use (2) parts PA10. P-61A-1s used R-2800-10 engines, which had a different ignition system than the R-2800-65s used by later p-61As and Bs.

 

Step 29

Part G11 is incorrect, there were no closing bulkheads at the rear of the main wheel wells-they were open to the interior of the tail booms. There should be six oxygen bottles at this location which are not provided with the kit.

 

Step 31

Delete parts PE2, PE3, Q1, Q3, Q5, Q8 and Q10 if showing controls in a neutral position. (Spoilers on one wing could be shown deployed in conjunction with appropriately defected ailerons and turned pilot’s control wheel.) Parts M1and C3, remove the stubs for the underwing hardpoints Most photos of P-61As do not show the wing edge lights, Parts X14 and X21. Some photos show the light positions covered with what could either metal covers or clear covers painted to match the overall scheme. (Edit 9/14/2013)

 

Step 33

Everything between the rear of the engine and the front of the firewall is fictional on this kit. The exhaust system, engine mounts, and lack of ductwork are all incorrect. Use of Part Q7 will make this unimportant because none of this will be seen (assuming that you paint clear Part WC1, of course.) If Part Q15 is used the rear of the exhaust stubs should be somewhat visible, but not having them will not be too noticeable. If any cowling or access panels are to be opened, however, major scratchbuilding will be required behind the engine for an accurate look. I now believe that all P-61s were fitted with underwing lights, part X25. (Edit 9/14/2013)

 

Part G17 is incorrect, there were no closing bulkheads at the rear of the main wheel wells-they were open to the interior of the tail booms. There should be six oxygen bottles at this location which are not provided with the kit.

 

Step 36

Delete parts PE1, PE4, Q2, Q4, Q6, Q8 and Q11 if showing controls in a neutral position. (Spoilers on one wing could be shown deployed in conjunction with appropriately defected ailerons and turned pilot’s control wheel.) Parts A3 and M6, remove the stubs for the underwing hardpoints. Most photos of P-61As do not show the wing edge lights, Parts X13 and X20. Some photos show the light positions covered with what could either metal covers or clear covers painted to match the overall scheme. (Edit 9/14/2013)

 

Step 38

Everything between the rear of the engine and the front of the firewall is fictional on this kit. The exhaust system, engine mounts and lack of ductwork are all incorrect. Use of Part Q14 will make this a moot point because none of it will be seen (assuming that you paint clear Part WC2, of course.) If Part Q16 is used the rear of the exhaust stubs should be somewhat visible, but not having them will not be too noticeable. If any cowling or access panels are to be opened, however, major scratchbuilding will be required behind the engine for an accurate look.I now believe that all P-61s were fitted with underwing lights, part X26. (Edit 9/14/2013)

 

P-61A-5

Follow steps for P-61A-1 except:

Step 2

Since these aircraft did not have the gun turret (see Step 21) I believe that you should delete the gunner's and R/O's gun sights, parts W1-4, W6-7, WW12, W26 and W32. You may also consider deleting the gunner's seat altogether, although I have read that turretless P-61s sometimes carried an observer in the gunner's position as an extra pair of eyes.(Edit 9/14/2013)

 

Step 20

Note that parts K39 and K41, or H16, N2 and N17, may be deleted if the gunner's seat is deleted in Step 2. (Edit 9/14/2013)

 

Step 21

Delete turret.

 

Step 23

Use blanking plate Part RA2.

 

Step 28

Use Parts PA11 and PA18 as shown, these are the GE “Turtleback” distributors used on the R-2800-65. Remove the magneto on the top of PA21 and fashion a rectangular blanking plate to cover the opening. The GE distributors had integral magnetos.

 

P-61A-10

No external differences from P-61A-5.

 

P-61A-11

Follow steps for P-61A-10 except:

 

Step 31

Part M1, remove the stub for the underwing hardpoint. Part C3, retain the stub for the underwing hardpoint. (Edit 9/14/2013)

 

Step 36

Part M6, remove the stub for the underwing hardpoint. Part A3, retain the stub for the underwing hardpoint. (Edit 9/14/2013)

 

P-61B-1

Step 2

Since these aircraft did not have the gun turret (see Step 21) I believe that you should delete the gunner's and R/O's gun sights, parts W1-4, W6-7, WW12, W26 and W32. You may also consider deleting the gunner's seat altogether, although I have read that turretless P-61s sometimes carried an observer in the gunner's position as an extra pair of eyes.(Edit 9/14/2013)

 

Step3

Delete parts Z15, Z16 and fill the hole in part K35, which is the pyrotechnic locker and should not have an oxygen hose attached to it.

 

Steps 4, 10, 11 and 12

Night binoculars were introduced on the P-61B, but are not included in the kit (nor are they included in either the Avionics or Eduard cockpit upgrade sets.)

 

Step 10

There should be an oxygen regulator and hose, similar to parts K25 and Z11, provided for the gunner.

 

Step 17

Delete part Z14, there should be an oxygen regulator and hose, similar to parts K25 and Z11, provided for the R/O.

 

Step 20

Note that Part SB1 does not have the correct configuration for a P-61B nosecone.

I have found very few photos of P-61Bs that show the air scoops, parts K30 and K31, fitted. Check your resources for the specific aircraft that you are modelling. Note that parts K39 and K41, or H16, N2 and N17, may be deleted if the gunner's seat is deleted in Step 2. (Edit 9/14/2013)

 

Step 21

Delete turret.

 

Step 23

Use blanking plate Part RA2.

 

Step 28

Use Parts PA11 and PA18 as shown, these are the GE “Turtleback” distributors used on the R-2800-65. Remove the magneto on the top of PA21 and fashion a rectangular blanking plate to cover the opening. The GE distributors had integral magnetos.

 

Step 29

Part G11 is incorrect, there were no closing bulkheads at the rear of the main wheel wells-they were open to the interior of the tail booms. There should be six oxygen bottles at this location which are not provided with the kit. But, if you modify the landing gear doors as described in Step 33, none of this will be readily visible.

 

Step 31

Parts C3 and M1, remove the stubs for the underwing hardpoints. Parts N12 and N14, fill in the seam lines for the aileron trim tabs. (Thanks to Mark H.) Many photos of P-61Bs do not show the wing edge lights, Parts X14 and X21. Some photos show the light positions covered with what could either metal covers or clear covers painted to match the overall scheme. Check your resources for the specifi aircraft you are building.(Edit 9/14/2013)

 

Step 33

Everything between the rear of the engine and the front of the firewall is fictional on this kit. The exhaust system, engine mounts and lack of ductwork are all incorrect. Use of Part Q7 will make this unimportant because none of this will be seen (assuming that you paint clear Part WC1, of course.) If Part Q15 is used the rear of the exhaust stubs should be somewhat visible, but not having them will not be too noticeable. If any cowling or access panels are to be opened, however, major scratchbuilding will be required behind the engine for an accurate look. Cut parts G32 and G42 along the line ahead of the wheel bulge. With the landing hear down the rear doors should be closed.

 

Step 34

Part G17 is incorrect, there were no closing bulkheads at the rear of the main wheel wells-they were open to the interior of the tail booms. There should be six oxygen bottles at this location which are not provided with the kit. But, if you modify the landing gear doors as described in Step 38, none of this will be readily visible.

 

Step 36

Parts A3 and M6, remove the stubs for the underwing hardpoints. Parts N13 and N15, fill in the seam lines for the aileron trim tabs. (Thanks to Mark H.)

 

Step 38

Everything between the rear of the engine and the front of the firewall is fictional on this kit. The exhaust system, engine mounts and lack of ductwork are all incorrect. Use of Part Q14 will make this unimportant because none of this will be seen (assuming that you paint Part WC2, of course.) If Part Q16 is used the rear of the exhaust stubs should be somewhat visible, but not having them will not be too noticeable. If any cowling or access panels are to be opened, however, major scratchbuilding will be required behind the engine for an accurate look. Cut parts G22 and G33 along the line ahead of the wheel bulge. With the landing hear down the rear doors should be closed. Many photos of P-61Bs do not show the wing edge lights, Parts X13 and X20. Some photos show the light positions covered with what could either metal covers or clear covers painted to match the overall scheme. Check your resources for the specifi aircraft you are building.(Edit 9/14/2013)

 

P-61B-2

Follow steps for P-61B-1 except:

 

Step 31

Part M1, remove the stub for the underwing hardpoint, Part C3, retain the stub for the underwing hardpoint.

 

Step 36

Part M6, remove the stub for the underwing hardpoint, Part A3, retain the stub for the underwing hardpoint.

 

P-61B-6

There are references in the P-61 literature to this model, but I have been unable to determine what its specific features were.

 

P-61B-10

Follow steps for P-61B-2 except:

 

Step 31

Part M1, retain the stub for the underwing hardpoint.

 

Step 36

Part M6, retain the stub for the underwing hardpoint.

 

P-61B-11

Follow steps for P-61B-10 except:

Step 2

Install the gunner's and R/O's gun sights, parts W1-4, W6-7, WW12, W26 and W32. (Edit 9/14/2013)

 

Step 21

Install turret with two machine guns.

 

P-61B-15

Follow steps for P-61B-11 except:

 

Step 21

Install turret with four machine guns.

 

P-61B-16

No external differences from P-61B-11.

 

P-61B-20

No external differences from P-61B-15.

 

P-61B-25

Gun-laying radar added, not aware of any external differences from P-61B-20.

 

Note: Some later As and early Bs were apparently fitted with gun turrets in the field, mostly fixed to fire forward and operated by the pilot. (Edit 9/14/13)

 

That's about it, at least for major visual differences among the variants. As always, check your references for the specific plane you are modeling, as individual airframes sometimes had non-standard factory or field modifications. Apologies for any errors and/or omissions, and any comments, additions, and/or corrections that anyone may wish to contribute are more than welcome.

 

Steve Sobieralski

Edited September 14, 2013 by Steve Sobieralski

[Derek B]

A very comprehensive and excellent list Steve - Thank you for taking the time and effort to compose it.

 

Derek

[LSP_Kevin]

A very comprehensive and excellent list Steve - Thank you for taking the time and effort to compose it.

 

Derek

 

Ditto!

 

Kev

[Dennis7423]

I noticed that the instructions for the Eduard P-61 Exterior Set show that the set comes with the correct gear doors for the P-61B.

[Dave Williams]

I noticed that the instructions for the Eduard P-61 Exterior Set show that the set comes with the correct gear doors for the P-61B.

 

Good catch. It's the undercarriage set.

 

http://www.eduard.com/store/Eduard/Photo-etched-parts/Photo-etched-set/P-61A-B-undercarriage-1-32.html

[mahernandez]

What about filling in the panel lines for the aileron trim tabs and fashioning the missing ribs for the fabric covering for the B model? Only the A's had the trim tabs.

 

Mark H

[Mark P]

Geez, is that all...

 

Nice, helpful list!

 

Mark Proulx

[Steve Sobieralski]

What about filling in the panel lines for the aileron trim tabs and fashioning the missing ribs for the fabric covering for the B model? Only the A's had the trim tabs.

 

Mark H

Forgot about that one Mark. Thanks.

 

I've edited the list to include this.

 

Steve Sobieralski

Edited July 21, 2013 by Steve Sobieralski

[Tnarg]

Thanks for an excellent list of fixes. This is a great example of why LSP is such a wonderful place.

 

Tnarg

[Heavens Eagle]

Superb list Steve!

 

I have this kit with the Eduard Big Ed  Set in my stash along with the resin weighted wheel set from Squadron.  I knew it was a decent kit but that it had issues, nice to know what the issues are!  

 

Many Thanks!!

[nmayhew]

Wow

 

Impressive list!!

 

Thanks for sharing

[Darren Howie]

Great post thanks for taking the time to put that list together.

[LSP_Ron]

Wow, We will have to add this to our tweak list. I am unable to right now as I am traveling.

 

Ron