Improve That Design: How Aircraft Could Have Been Made Better

Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules

The SBDs at Midway got lucky, their success won by the sacrifice of dozens of torpedo bomber crews and land based dive bombers.
Nothing occurs in a vacuum.
A5Ms were shooting down SBDs in the Marshalls in February 1942, Zeroes claimed quite a few at Coral Sea and in the Solomons. They weren't invincible.
 
if you would bulid it like i said it would have been better
 

Let me dispel a myth or two from a bit more modern era. Contrary to what Tomcat guys claim, the AIM-54 was not the end all be all missile. It was designed to kill large, mostly unaware bomber aircraft from great distances. It was used in combat by the US only twice, both in 1999, all missiles fired missing. The Iranians had a bit more success, claiming 70+ AIM-54 kills against... Iraqi's. Use Operation Desert Storm Iraqi Air Force statistics as a measuring tape to their training proficiency.

What the F-14s radar, the AWG-9, was designed to do was launch AIM-54s out of a radar mode known as TWS (Track While Scan pronounced TWiS). TWS allowed targeting of multiple aircraft by one (aircraft) or Tomcat. In the early 90s, when I first started fighting them it was call Track While Lie. Other TWS equipped fighters radar would tell (indicate to) the pilot when it had low confidence something was actually being tracked. Not the Tomcat. TWS also fooled most Radar Warning Receivers (RWR) on fighters until the advent of the ALR-56C on the F-15C model. I spoke with my Kadena buddies about fighting it in large force exercises (LFEs). The consensus was not good. They routinely called kills and no one was near where they thought their opponent was (hence the Track While Lie reputation). Also of note is their radar was High Pulse Repetition Frequency (HPRF) only. HPRF only sees things closing towards it, and in the case of the AWG-9, did not do well over land either. Targets maneuvering near the beam or less aspect it REALLY had a tough time. The F-15 & F-18 have radars that are both HPRF and Medium PRF (MPRF) and use it in an interleaved manner. The F-16 is MPRF only. MPRF handles aircraft maneuvering VERY well, especially compared to HPRF only.

I have fought them in much smaller scale fights, and the results where decidedly lopsided. In one of my squadrons we were not allowed to do check rides with them as the adversary. I have fought them in BFM, with both the original and GE motors. The GE powered version could be work in a slow speed fight, but not insurmountable. The original engines were way too small for that airframe. Wings pop out at a certain speed, it's limited to 7Gs, it has two people in it, it's huge, and it's over hyped. Look at it's thrust to weight, and compare that to any radar equipped fighter that came out of the US or Russia starting in 1974 (F15, F16, F18, MiG-29, Su-27) and note that none of them, or anything made since, have wings that swing or HPRF only. It was technologically advanced for late 60's, early 70's. After about 1974, not so much.

And the classified summary of its short comings was long as well.

However, it did do some good work once they hung bombs on them.

As was written earlier, the stories are large and written at a time when no one countered them (because we didn't want anyone to really know how bad it was). Get a group of non Tomcat fighter pilots together, and ask them which fighter was the least threatening, and the answer will be the F-14.

Cheers,
Biff
 
Hey BiffF15,

Did you ever get to play with the F-14D? The reason I ask is due to the radar being replaced with the APG-71, and the upgraded JTIDS system. I realize that the engines still did not raise the T/W ratio much past 1:1 at dogfight weights, but I believe the radar upgrade included all the bells and whistles that the APG-71 had, plus a few unique to the F-14D. I also wonder how much help the improved IRST would be.
 
The SBD is a bit over rated, not in what it did, which is beyond dispute, but in some of the "book" figures which crop up all too frequently.

The often quoted 2250 lb bomb load consisted of a 1600lb AP bomb, which so far nobody can find a record of the SBD dropping in action, and two 325lb depth charges, which is certainly an odd combination. It also would have meant an operational radius a tiny bit more than the visual horizon. A US Navy data sheet lists the SBD-5 as holding 254 gallons with a 1000lb bomb and 165 gallons with the 1600lb bomb. Yes, lots of Navy documents list the 1600lb but actual use??
Now unless you exceed max gross weight hanging those 325lb depth charges under the wings calls for leaving 108 gallons of fuel out out of the tanks from that 165.
53 gallons to take off, fly to target, climb to bombing height on the way, execute dive and run for home????????

Makes the P-PTMNBN (Plane That Must Not Be Named) look long ranged

The Use of the SBD as a "fighter" needs to be looked at also. Yes it was used, but for how long or how many times?
Was it ever used after the Battle of Coral Sea? I don't believe it was used as a CAP during Midway or after? I could be wrong.

it is a nice little factoid but doesn't really reflect the capabilities or use of the plane over the vast majority of the war.
 

Thomas,

I never fought them, as they were a West Coast based asset (and less than 60 made). The APG-71 as far as I remember, was HPRF only. I read online that it was both HPRF and LPRF (not sure if Low actually means Medium or not). I don't think they were ever equipped with AIM-120's either. As for the GE engines, they were the same in the D as well as the B (or A+) IIRC. As for the JTIDS (Joint Tactical Information Distribution System), it's the Cats Meow. I flew with a detuned version of it in the Eagle, called FDL (Fighter Data Link). The Eagle was originally scheduled to get JTIDS (and one squadron did), it was subsequently replaced with a less expensive and slightly less capable FDL. I can't comment about the IRSTS as I did not fight them.

From what I remember it didn't have all the capabilities that the APG-70 had from the get go, which is a shame (they should have paid for it). The APG-70 was a large leap over the APG-63 (both original and MSIP or Programable Signal Processor versions). The APG-63V1 was new boxes, same old radar dish. The APG-63V2 was the first Eagle to fly with an AESA (Active Electronically Scanned Array), and the APG-63V3 was a much improved AESA over the V2. Those latter radars (V1, 2, & 3) are eye watering in capability. EYE WATERING.

Once the Eagle started flying with AESA radars was the first time to my knowledge that we had Red Flags where no blue air was lost to red air. And that is unbelievably HUGE.

Cheers,
Biff
 
Was it ever used after the Battle of Coral Sea? I don't believe it was used as a CAP during Midway or after? I could be wrong.

During the battle of Midway, Yorktown's SBDs were used as CAP while the F4Fs were vectored out to intercept the inbound force from Hiryu.

While not a gun-slinger, the SBD did, on several occasions, prove it's worth as supplemental CAP by intercepting B5Ns and D3As.
 
Thoughts on a thin wing Hurricane?
Gone over it before.

Fuel tanks between front and back spars. Landing gear fits, mostly in the fuselage/wing center section.


You might be able to use thinner outer wings but that may not give the desired improvement. Making the center section (out to the landing gear attachment points) thinner may have required too much work/rework. Plane would no longer be a Hurricane.

Hurricane was practically a STOL machine once it got the constant speed prop. It could be at 50ft above the runway hundreds of feet before most US army fighters even got the wheels of the ground. Would the extra speed of the thin wing make up for the greater take-off and landing distances (fewer airfields to use? )
 
What advantages come with direct injection vs. the pressure carburetor?

I'd guess better metering of fuel to each cylinder.

Incidentally why later R-3350s went to direct fuel injection - poor mixture distribution in earlier models.


I'm guessing having an X-cylinder with 2-sets of 60-degrees between them top and bottom would be more difficult to pull off?

No more than any X-engine, though balancing could be an issue.


What's a master and slave type rod, and what would make it weaker than the twin-crankshafts of the X-3420?

Master and Slave rods are what is used by radials. It was also used, on occasion, on in-line engines. The Rolls-Royce R in 1929 ran with fork and blade rods, like the Buzzard it was based on, but the 1931 version was converted to master and slave rods because of big end bearing failures.

The master rod is connected to the crankshaft. The master rods are connected to the master rod.

Master and Slave Rod


Fork and Blade Rods



From Connecting rod - Wikipedia

Not sure if you can say that one is stronger than the other. There are downsides to both.

The twin crank solution adds weight, and requires gears to join the crankshafts together, but simplified other parts of the engine, such as using the same blocks, heads and intake manifolds as the base Vee engine.

The downside to master and slave rods is that the pistons don't have the same stroke, so extra tuning may be required.

The Vulture had master and slave rods, with the big end bearing on the master rod causing a lot of problems, probably the last major issue the Vulture had to be solved at the time of its cancellation.


How much earlier would you have guessed?

How early would the Army have fully committed to the V-3420? That is the real question, since Allison was not big enough or willing to develop engines without the prospect of sales.
 
Last edited:
How early would the Army have fully committed to the V-3420? That is the real question, since Allison was not big enough or willing to develop engines without the prospect of sales.
Quite correct .

The Army, at one point in 1939 owed Allison something like 900,000 dollars for work already done. They never paid it.

In order to get permission to build the Export engines for the French and British P-40 orders (Hawk 81) Allison had to agree to forgive the debt.

Allison at some point in 1939 had a grand total of 25 people working in the engineering section and that include two guys that ran the blueprint machine.

any and all suggestions that Allison "JUST" do such and such need to be looked at in that light.

GM had loaned (put in ) over 1/2 million dollars into the V-1710 program and had not the Army ordered the engines for the 524 P-40s in April of 1939 GM was considering shutting down the program.

Allison was running a highly successful bearing manufacturing operation. many people do not understand how massive the build up of some American companies was.

year..........................end of year employees
1937........................322
1938........................530
1939........................786
1940......................4,303
1941.....................9,763
1942..................14,323
1943..................23,019

Number of employees includes the Bearing division.

There is reason to believe that Allison could not have done what it did as far as building the engines it did build if it had spent much more time on side projects or not built the engine in a somewhat modular fashion.
 
It was a SBD rear gunner who put Saburo Sakai out of action for quite a while.
Actually, according to Sakai's own book (with Caudin), it was the rear gunners of a flight of TBFs that did the deed. Spotted from a distance through his soda pop encrusted canopy, he mistook them for F4Fs and raced in to bounce their six. OOOPS! Popping a soda bottle cap at 20,000 feet has certain undesirable effects.
 
There is reason to believe that Allison could not have done what it did as far as building the engines it did build if it had spent much more time on side projects or not built the engine in a somewhat modular fashion.

I don't think that the modularity was a problem.

But having to do the base engine (with the long nose, C series engines) plus remote gearbox drives (D series engines) for pusher aircraft (YFM), remote gearbox (E series engines)for tractor aircraft (P-39), opposite hand engines (for P-38), plus the fuel injection project and X-3420/V-3420 work must have put a lot of strain on the small design team, and slowed the development of the core engine. And all this before they got substantial orders from the Army.
 

Users who are viewing this thread