P-61 or Reverse Lend Lease Mosquito

[stona]

Electronic units work well in dark, cool environments, especially early radar units. .

Not too cool! Bomber Command crews were obliged to turn on and warm up H2S sets before climbing to operational altitudes as it was too cold at altitude for the components (I assume this refers to the valves) to reach their operating temperatures.
Cheers
Steve

 

[FLYBOYJ]

Not too cool! Bomber Command crews were obliged to turn on and warm up H2S sets before climbing to operational altitudes as it was too cold at altitude for the components (I assume this refers to the valves) to reach their operating temperatures.
Cheers
Steve

Depends on the internal components - cathode tubes, yes, but once up and running you need stabilized cool temperatures. With almost 20 years working around P-3s on and off, the coolest place on the flightline on a hot day was inside an aircraft that was going though ground avionics checks, but then again, we were dealing with components made up of PCs rather than old cathode tubes.

 

[pinehilljoe]

Depends on the internal components - cathode tubes, yes, but once up and running you need stabilized cool temperatures. With almost 20 years working around P-3s on and off, the coolest place on the flightline on a hot day was inside an aircraft that was going though ground avionics checks, but then again, we were dealing with components made up of PCs rather than old cathode tubes.

Did the early P-3s have vacuum tubes? It must have been a struggle to keep the first AI sets operating night after night with shocks from landing.

 

[FLYBOYJ]

Did the early P-3s have vacuum tubes? It must have been a struggle to keep the first AI sets operating night after night with shocks from landing.

I don't know - most of my time were on P-3Cs Update IIIs, about the last 150 built. By that time most if not all of the electronics had PCs

 

[fastmongrel]

The P-61E was a day fighter and replaced the radar with 4 x 0.5" mgs.

Interesting I wonder what role the USAAF had in mind for it.

 

[FLYBOYJ]

From Wiki...

"Two P-61B-10s (numbers 42-39549 and 42-39557) converted to daytime long-range escort fighters. Tandem crew sat under a blown canopy which replaced the turret, additional fuel tanks were installed in place of the radar operator's cockpit in the rear of the fuselage pod, and four 0.50 in (12.7 mm) machine guns took place of the radar in the nose (the 20 mm/.79 in ventral cannon were retained as well). First flight 20 November 1944, cancelled after the war ended. The first prototype was converted to an XF-15, the second lost in take-off accident 11 April 1945."

 

[GrauGeist]

The P-61E was a day fighter and replaced the radar with 4 x 0.5" mgs.

Interesting I wonder what role the USAAF had in mind for it.

There were only two XP-61E types built for evaluation. They were actually P-61Bs that had the turret removed, additional fuel tanks to extend their range and the radar removed and replaced with four .50 MGs while retaining the four 20mm cannon.

The purpose for the XP-61E was to be a long-range escort heavy fighter.

 

[Milosh]

 

[GrauGeist]

A really good book on the P-61 is "Northrop P-61 Black Widow: The Complete History and Combat Record" by Campbell/Pape (ISBN: 978-0887407383)

It's paperback, but loaded with excellent info

 

[Timmy P3B FCO]

I don't know - most of my time were on P-3Cs Update IIIs, about the last 150 built. By that time most if not all of the electronics had PCs[/QUOTE

Hello,

P3B's and P3C's Update I,II, II.5's all had tubes in the VOR (ARC101?) receivers. If I remember correctly, The ARC 101 also had dual use of VHF receivers along with VOR (VHF Omni Directional) functions. I flew as FCO and IFT on P3B's and P3C's (UD II, II.5, III) from 1990-2007. ARC 101's were replaced over time, but they were around well past 2000............(as far as I remember)

Of the many heat sensitive items on the plane (acoustic station in P3B's) was the most sensitive. We would take the rack doors off the equipment bays to cool the equipment while chasing subs. I think we also did that on P3C UDII, II.5 DIFAR systems but memory..........

Timmy
VP-92

 

[FLYBOYJ]

Hi Timmy! VP-92? I was in VP-65

 

[XBe02Drvr]

Did the early P-3s have vacuum tubes? It must have been a struggle to keep the first AI sets operating night after night with shocks from landing.

I lived for a time next door to VX-1, the Navy's airborne ASW equipment test and evaluation squadron, rode in their planes, drank with their troops. For awhile they had P-3As, -Bs, and -Cs on board at the same time, as they had to test backward compatibility of each new system. The "A" model, a child of the late 50s/early 60s, was rife with vacuum tubes in practically all its equipment, and had a VERY primitive inertial navigation platform and computer. Its ASW attack plot was largely manual ( a la P-2 Neptune), without the extensive computerization of later models. The "B" had a lot more solid state circuitry and a (wow!) DIGITAL computer! It still had plenty of tubes, however, especially in the NAV/COM equipment. The "C" was mostly solid state, but still had some older equipment on board. I don't remember hearing a lot of complaints about tubes with respect to reliability, but a lot of grousing about how long it took to erect and stabilize the INS. Up to 24 hours in some cases, out on the compass rose hardstand, with APU running and some poor stiff out there standing watch. The tube circuitry was all ruggedized the way jet fighter radar was with reinforced circuit boards and bracket/heatsinks supporting the tubes. P-3s didn't have AI (Airborne Intercept) Radar, they had Airborne Surface Search. (You can make any acronym out of that you wish!)

 

[Old Wizard]

 

[FLYBOYJ]

When I worked on P-3 production flight line in Burbank, I remember a lot of PC boards in drawers by the TACCO and NAV/COM stations. I remember some of the avionics guys working on them and sometimes slamming the drawers to get the PC boards to seat. Fast forward a few years later while i the reserves, all of my time was spent playing with props and engines.

 

[fubar57]

From Wiki...

"Two P-61B-10s (numbers 42-39549 and 42-39557) converted to daytime long-range escort fighters. Tandem crew sat under a blown canopy which replaced the turret, additional fuel tanks were installed in place of the radar operator's cockpit in the rear of the fuselage pod, and four 0.50 in (12.7 mm) machine guns took place of the radar in the nose (the 20 mm/.79 in ventral cannon were retained as well). First flight 20 November 1944, cancelled after the war ended. The first prototype was converted to an XF-15, the second lost in take-off accident 11 April 1945."

XP-61E, 42-39549

From Northrop P-61 Black Widow by Miroslav Balous, Motorbook International

 

[Old Wizard]

 

[swampyankee]

The USAAF did operate Mosquitoes and Spitfires, so reverse-lend lease certainly existed. I think the Mosquito was, overall, a better airplane but the P-61 was probably a more capable

I think that the turret and 3-man crew on the P-61 were also a design flaw. Getting rid of the turret and the 3rd crew member would have resulted in much higher performance, as was the case with the P-61E and F-15 variants.

 

[Shortround6]

The P-61E and F-15 variants got a lot of their performance increase from the turbocharged "C" series engines (very similar to the engines used in the P-47M & N) and not by ditching the turret and crewman.
Some books claim about a 5mph difference in speed between early P-61s built without the turret (around 300) and the ones with turrets.
Climb could well have been affected.

 

[wuzak]

The P-61E and F-15 variants got a lot of their performance increase from the turbocharged "C" series engines (very similar to the engines used in the P-47M & N) and not by ditching the turret and crewman.
Some books claim about a 5mph difference in speed between early P-61s built without the turret (around 300) and the ones with turrets.
Climb could well have been affected.

The two XP-61Es were converted from P-61Bs.

Northrop XP-61E Black Widow

The F-15 was based on the P-61C, which had the turbocharged engines.

Northrop F-15 Reporter

The tell-tale is the lack of ducts on the side of the engine cowling

XP-61E

F-15

From Joe Baugher's site, it appears that the XP-61E was around 6-7mph faster than the P-61A/B.

On the other hand, the P-61C was capable of 430mph, and the F-15 similar, or the same.

 

[tomo pauk]

The USAAF did operate Mosquitoes and Spitfires, so reverse-lend lease certainly existed. I think the Mosquito was, overall, a better airplane but the P-61 was probably a more capable

I think that the turret and 3-man crew on the P-61 were also a design flaw. Getting rid of the turret and the 3rd crew member would have resulted in much higher performance, as was the case with the P-61E and F-15 variants.

If the P-61 was designed without the turret and designated gunner & his cockpit, the resulting aircraft could've been both smaller and lighter. The central pod losses the superimposed gunner's quarters, meaning lowering the drag further. Hopefully the resulting aircraft would've been just a bit bigger than the F7F, with a turn of speed around 400 mph.

Alternatively, accept (X)P-65 proposal from Grumman, but with R-2800 engines and no turbo.