X-Plane-of-the-Day

[NorthAmericanAviation]

6 hours ago, MiffedStarfish said:

Tomorrows craft:

No idea. Help me out on this one, @Servo?

Here's the complete roster: https://docs.google.com/spreadsheets/d/1pxbH4AyQhn62Rb5ZNawKfkscsO47rq4DhVh1xgbJJqY/edit#gid=0

[MiffedStarfish]

2 hours ago, YoeriCookie said:

It uses tweakscale, doesn't it?

What? No. What part do you think is tweakscaled?

@qzgy thanks, I'll edit that in.

[YoeriCookie]

4 hours ago, MiffedStarfish said:

What part do you think is tweakscaled?

Little heatshields on the tail, intakes look out of proportion with the stock fuselage too. Sorry if wrong but they just don't seem stock

[MiffedStarfish]

It might look a bit wrong due to the camera angle, but it is definitely Stock. I don't have any part mods installed, just EVE and scatterer. 

[qzgy]

8 hours ago, YoeriCookie said:

Little heatshields on the tail, intakes look out of proportion with the stock fuselage too. Sorry if wrong but they just don't seem stock

Yeah, stock has those 0.625 m heat shields that were used on the back. However, from the reference picture, doesn't seem as if the actual craft had those. Care to explain, @MiffedStarfish?

[MiffedStarfish]

Oh that's strange, I must have accidentally used a photo of a prototype version or something. You can see them here in this picture:

[qzgy]

Huh. Ok then, that makes sense. It shouldn't really matter anyway, just aesthetics.

[YoeriCookie]

7 hours ago, qzgy said:

0.625 m heat shields

I never even knew they existed...

[Munbro Kerman]

April 1947: Douglas D-558-I "Skystreak"

Along with the X-1, the D-558-1 served top collect research data at transonic speeds. it was given a real elevator surface thinner than the wing to mitigate transonic shockwave collisions between the two surfaces. The aircraft were light, carrying a J-35 engine and 230 gallons of fuel. there were no protruding surfaces on the plane; the pre- area-rule thinking of slick, bullet shaped lines is very present.

The Skystreak was part of a three-step program from the U.S. Navy and Douglas. The second stage would be the D-558-II, and the third stage never came through to fruition. One of the main focuses of the first stage was to gain data on pressure distribution and transonic buffeting. This aircraft, along with the X-1, were the only way to gather data for aircraft traveling at the speed of sound until NACA was able to develop more powerful wind tunnels.

Download Link:

https://kerbalx.com/MunbroKerman/D-558-1-Skystreak

Tomorrows' Craft:

@NotAnAimbot's XB-46

Info Sources: Crossfield, A. Scott, and Clay Blair. Always Another Dawn. Salem, NH: Ayer Pub., 1990. Print.
Dunbar, Brian. "NASA Dryden Fact Sheet - D-558-I." NASA. NASA, 01 Apr. 2015. Web.

[NotAnAimbot]

Posting this now since I won't have time to tomorrow.

April 1947: Convair XB-46

Description sourced from https://en.wikipedia.org/wiki/Convair_XB-46

Aware of advancement of jet bombers in Germany, the U.S. War Department issued a requirement for medium bombers weighing from 36 to 91 tons. One of the several designs built to fulfill it was Convair's XB-46 bomber, which was built as a single mostly unarmed prototype to test air maneuvering. 

First flight occurred on April the 2nd 1947, after a month of taxi testing. Stability was found to be satisfactory, although there were problems with de-icing, the cabin air system and oscillation in the wings. Control surfaces were moved by a pneumatic system, which was unusual considering most contemporary planes used manual, electrical or hydraulic systems. Maximum bombload was of 20 000 pounds, in addition to two M2 12.7mm machine guns mounted in the tail.

Although eventually accepted for service, no B-46s were produced for the design was already obsolete by August 1947, where the XB-47 and XB-45's planned performances would eclipse the B-46's. Ground testing on aerodynamics and the unique pneumatic system continued at several bases until 1951, where the nose section was donated to the U.S. Air Force museum at Ohio. The rest of the fuselage was scrapped in 1952.

Builder's notes

Sorry for my ex-fellow toaster users, this plane has over 400 parts due to the triple Mk2 fuselage and the pretty complex engine pods which I couldn't get entirely correctly. The plane has a slightly lower top speed than the real deal, but weighs over twice as much at about 90 tons, requiring me to use 16 (If my memory is correct) Wheesleys to propel it. Action group 1 toggles the flaps, while action group 5 toggles the cargo bay and staging past the engines drop bombs. 

Flight handling is what you'd expect from a medium/heavy bomber, which means relatively sluggish controls especially in pitch.

Download link

https://www.dropbox.com/s/qyf294ir9r4cnff/XB-46.craft?dl=0

 

Next up: XB-48 by @Servo

Edited May 27, 2017 by NotAnAimbot

[qzgy]

Nice, for both craft!

@NotAnAimbot, have you considered radiator panels for finishing that engine nacelle?

[NotAnAimbot]

4 hours ago, qzgy said:

have you considered radiator panels for finishing that engine nacelle?

Not really, since I rarely use radiators at all in my builds. I might try it on other replicas.

[qzgy]

13 minutes ago, NotAnAimbot said:

Not really, since I rarely use radiators at all in my builds. I might try it on other replicas.

I tend to find them useful for some curved things. Sometimes though, there isn't anything that can really help.

[Servo]

Keeping up the pace here. I'll make my contribution for the day as well. I figure that if we can upload two craft in a day, all the better. We've got a lot of craft, so anything we can do to get ahead is for the better. Don't expect it, though.

June 1947 - Martin XB-48

The Martin XB-48 was a prototype jet bomber built to compete for a spot as the U.S.’s first operational jet bomber. It followed on the footsteps of the Douglas XB-43 Jetmaster, and was a much larger and more advanced design. It was powered by six General Electric J47 engines, required due to the low thrust output of the early designs. Interestingly, although it appears that the engines are in three separate nacelles, they are actually connected by a series of air ducts incorporating airflow between the engines as well as through the inlets. This was designed to improve cooling, something that the early engines had trouble with.

The XB-48 was part of the Class of '45, a trio of jet bombers developed in 1945 in response to Germany’s Amerika Bomber program and a similar program in Japan. Both programs were looking for long-range jet bombers capable of intercontinental sorties. The other planes in the class were the Convair XB-46 and the North American XB-45, the latter of which was produced as the B-45 Tornado. However, all three planes were rapidly outclassed by the Boeing B-47 Stratojet. This is mainly because the three planes borrowed heavily from research on straight-winged piston bombers in WWII. For example, the XB-48 borrows heavily from the Martin B-26 Marauder.

Builder's notes:

The XB-48 handles pretty well once airborne, but you have to be really careful taking off. Wait until you are going faster than 100m/s before beginning to pitch up, then do so slowly. As soon as the rear wheels leave the ground, pitch up harder to gain altitude.

Download Link:

https://kerbalx.com/servo/Martin-XB-48

Tomorrow's Craft:

@Munbro Kerman's Northrop XB-49

[Munbro Kerman]

October 1947: Northrop YB-49

A prototype jet-powered bomber derived from the earlier Northrop YB-35, the YB-49 included the flying wing design. Although the YB-49 never entered service for the US Air Force, its design proved to be valid and would be incorporated with the much later B-2 Stealth Bomber. In 1944, Northrop's XB-35 program was behind schedule immensely, and the Air Force cancelled the contract. But, the flying wing design proved to interest the Air Force and they continued to test a single XB-35 prototype. 

Two air frames built for the supposed XB-35 program, the Air Force ordered for them to be fitted with jet engines; thus giving birth to the YB-49. Testing proved to even more promising than the XB-35. The later B-2 bomber would have the same wingspan of the YB-49: 172 feet. Flight data recorded from the YB-49 would be used to help design the B-2 Spirit in the 1990's. 

Download Link:

https://kerbalx.com/MunbroKerman/YB-49-Flying-Wing

Tomorrows' Craft:

@NorthAmericanAviation's D-558-II

[qzgy]

Cool. How are flight characteristics?

[NorthAmericanAviation]

February 1948: Douglas D-558-II "Skyrocket"

In 1948, Douglas presented the Navy-funded D-558-II to NACA at Muroc Airfield (Edwards AFB). The plane was designed with a swept wing, and was intended to reach speeds up to Mach 1.25. Needless to say, it exceeded expectations. 313 flights were made among the 3 Skyrockets built—123 in #1, 103 in #2, and 87 in #3.

The D-558-II was the second stage of what was originally planned to be a 3-stage program, the third being the Skyflash. Flights were made to collect data on pressure distribution, structural loads, and structural heating at transonic speeds. Later flights examined ‘high-speed instability,’ specifically the tendency for transonic aircraft to pitch up without pilot input. By extending the effective wing chord with slats, this pitch-up was stopped.

 

Race for the Next Mach Number

           After Chuck Yeager broke Mach 1 in the Bell X-1, there was no initial publicity for this event, except that which spread around Edwards AFB and Happy Bottom Ranch. Soon after, a competitor to both Yeager’s speed record and skill as a pilot arrived: A. Scott Crossfield. A civilian engineer with a masters in Aeronautics, 29 at time of arrival, he would fly the X-1, X-4, X-5, X-15, XF-92, D-558-I, and of course the D-558-II in his time at Edwards. His skill as a pilot and background as an engineer made him an excellent test pilot, logging many more hours than most (if not all) test pilots then active at Edwards. Naturally, a competitive atmosphere developed around Crossfield and Yeager, both pilots talking to the Navy and Air Force, respectively, looking to reach the next Mach number, speed record, etc. For Crossfield, his aircraft for reaching Mach 2 was the Douglas Skyrocket—it was a swept-winged mixed power rocket plane, relying on a single J-35 for the initial stage, then transitioning to power under a Reaction Motors, Inc. LR-11 four-chamber Oxy-Alcohol rocket engine. In November 1953, Crossfield won the battle for Mach 2 when he reached Mach 2.005, 682.3m/s, 1291mph in the Skyrocket. For the successful flight, there was no jet engine propulsion in the D-558-II #3, only the sealed system of the LR-11. All four chambers were fired upon release from the mothership Boeing P2B/B-29, and he piloted the plane to 72,000ft. Upon reaching said altitude, he put the plane in a steep dive. The plane remained stable and reached Mach 2, even though it was not designed for that speed. Crossfield, then 32, was celebrated in the press and media following his flight.

Download Link
https://kerbalx.com/NorthAmericanAviation/Douglas-D-558-II-Skyrocket-+-P2B-Mothership

Tomorrow's Craft: @Servo's McDonnell XF-85 "Goblin"

Edited May 31, 2017 by NorthAmericanAviation

[Servo]

Continuing on a trend of drop-tested craft, here's my rendition of the XF-85 Goblin

November 1948 - McDonnell Douglas XF-85 Goblin

The McDonnell Douglas XF-85 was one of the more successful attempts at parasite fighters through history. The concept of a parasite fighter, a small plane carried within a much larger aircraft, has been attempted many times with large bombers, and in some cases, airships. After World War II, the U.S. military saw the strategic value in long-range heavy bombers such as the B-29, and sought to leverage them as a nuclear deterrent during the Cold War. However, to protect the large bombers, fighter airplanes were needed that had the range to keep up with the giants of the skies. This led to a renewed interest in the concept of the parasite fighter, allowing bombers to carry their own short-range craft within their massive bomb bays, releasing them when the enemy tried to intercept them. The fighters could then be recovered on trapezes which would then retract, hauling the craft back into the bomb bay of the host aircraft.

The concept of the parasite fighter has always been plagued with the problem of recovering the fighter, something with only got harder with the increased speeds of jet bombers. Trapezes were necessary to allow the fighter to fly outside of the turbulent air caused by the large bomber, leading to mechanical issues. Additionally, the disturbed air formed in a much larger air than was expected, leading pilots to comment on how difficult it was to recover planes. In several attempts with the XF-85, the closest the pilot came to recovering his aircraft was when he cracked the windscreen on the trapeze. All attempts ended in the pilot belly-landing the XF-85.

As the B-36 was still in the prototyping stage during the XF-85 testing, all tests were undergone using a modified B-29. The B-36 was much larger, allowing the XF-85 to be carried completely within the bomb bay. Unfortunately, the combination of the difficulties of executing a full launch - flight - recovery sequence, as well as the Soviet emphasis on surface-to-air missiles made the concept of the heavy bomber, as well as that of the parasite fighter, obsolete by the beginning of the 1950s. As a final nail in the parasite fighter's coffin, the practice of aerial refueling meant that fighters and bombers could be kept airborne almost indefinitely, meaning that bombers could focus on carrying heavier bomb loads rather than defensive fighters.

 

Download Link:

B-36J and XF-85:https://kerbalx.com/servo/Convair-B-36J-Peacekeeper

XF-85 (standalone): https://kerbalx.com/servo/XF-85-Goblin

Tomorrow's Craft:

@Munbro Kerman's Convair XF-92

 

[DMSP]

9 hours ago, Servo said:

November 1948 - McDonnell Douglas XF-85 Goblin

Wonderful! Glad I finally caught along this thread. You guys make some great stuff.

[Munbro Kerman]

September 1948: Convair XF-92

A design that was used for experimental purposes only, the XF-92's delta-wing design would go on to be used in aircraft such as the F-102 Dagger, F-106 Dart, and the US Navy F2Y Sea Dart. The US Air Force requested a supersonic interceptor that was able to reach 50,000 feet in under four minutes. Multiple companies put forth their design, including Consolidated Vultee (later known as Convair). Their design, which included swept wings, showed multiple problems during testing in wind tunnels. German scientists from Operation Paperclip were doing research on delta-wing designs, which Convair considered. They modified their design and included delta-wings. When they presented their improved design, the Air Force approved, giving birth to the XF-92.

During testing, Chuck Yeager was assigned to the XF-92, where he discovered that he was able to pull his nose up to a 45-degree angle without stalling during landing. After a new engine was implemented to the craft, Yeager noted that there was very little improvement to the handling of the craft: everyone commented that it was severely underpowered. Scott Crossfield noted that "no one wanted to fly that plane...it was a miserable flying beast." Though the craft had its cons, it also had its upsides. The large surface area of the delta-wing design gave the craft a very good low-speed performance. 

Download Link:

https://kerbalx.com/MunbroKerman/Convair-XF-92

Tomorrows' Craft:

@Munbro Kerman's McDonnell Douglas XF-88 Voodoo

[Munbro Kerman]

October 1948: McDonnell XF-88 Voodoo

The XF-88 started from a request from the USAF to create a long-range fighter to escort bombers. It was also to be a replacement for the P-51 Mustang, which was a WWII bomber escort. The Voodoo had a thirty-five degree swept wing, and two engines that were housed in the lower fuselage. The engines proved to be underpowered and were replaced with more powerful engines that included afterburners.  

 

This increased the speed from 614 mph to 700 mph, improving the overall performance of the aircraft. The XF-88 was chosen over the XF-90 and YF-93 to be built as a "penetration fighter" to escort bombers. Shortly after the Air Force changed plans before production started, and the project was cancelled. Years later the XF-88's design would be enlarged to be developed into the F-101, where the F-101 would be used in the Korean war and Vietnam war.

Download Link:

https://kerbalx.com/MunbroKerman/McDonnell-XF-88-Voodoo

Tomorrows' Craft:

@Munbro Kerman's Northrop X-4 Bantam Tailless Aircraft

[Munbro Kerman]

December 1948: Northrop X-4 Bantam Tailless Aircraft

The X-4, not using any horizontal stabilizers, was a twin-engine experimental jet to test how an aircraft can perform at Mach 1 without any horizontal tail surfaces. Flight control systems at the time did not help the X-4's situation when the tailless craft was deemed unsuitable for supersonic flight.  

 

This increased the speed from 614 mph to 700 mph, improving the overall performance of the aircraft. The XF-88 was chosen over the XF-90 and YF-93 to be built as a "penetration fighter" to escort bombers. Shortly after the Air Force changed plans before production started, and the project was cancelled. Years later the XF-88's design would be enlarged to be developed into the F-101, where the F-101 would be used in the Korean war and Vietnam war.

Two aircraft were built, with the first craft flown for only 10 flights before it was said to be "mechanically unreliable." The second craft would be flown 20 times, being tested by Chuck Yeager, Scott Crossfield, and others. Crossfield noted that as the X-4 gained speed, the nose would pitch down, which also happened to the Me-163 Komet; a German version of a tailless craft. 

Balsa wood strips would be added and removed over time to see if it would improve the craft's stability, in which it did. Fuel leakages in the wings caused the aircraft to be grounded for five months, and another three months after one of the engines were damaged during landing. Both aircraft survived the testing, and are now on display. The X-4's main goal was to show that a tailless craft could be flown above Mach 1, and it failed to reach that goal. Years later, however, the F7U-Cutlass would prove that a tailless craft can fly stably above Mach 1. 

Download Link:

https://kerbalx.com/MunbroKerman/X-4-Bantam

Tomorrows' Craft:

@Servo's XF-91

[Servo]

June 1949 - Republic XF-91 Thunderceptor

The Republic XF-91 Thunderceptor was a prototype supersonic interceptor, designed to rapidly engage high-flying enemy bombers. It was the first U.S. fighter to break the speed of sound, and it was a revolutionary design for its time. The reverse-chorded wings combated the violent pitch-up that occurred on swept-wing fighters passing through transonic speeds. This pitch-up was known as the "Sabre Dance", thanks to the F-100 Super Sabre's (this occurred on most other early swept-wing jets, the F-100 was later but better known) notorious tendency to rapidly nose-up when approaching Mach 1. This occurred because the airflow separated from the wingtips before the wing root. This caused the tips to loose lift, meaning that the center of lift rapidly shifted forwards. This problem was exacerbated by the underpowered engines that powered early jet aircraft. The F-91's reverse-chorded wing combated this by causing the center of lift to shift backwards as the flow began separating, making the plane more stable in transonic flight.

The two XF-91s that were built. The Thunderceptor underwent heavy design changes as it was prototyped. On the left, the plane has been modified with a radome, and on the right, the XF-91 has been modified with a V-tail.

The XF-91 was designed as an interceptor, meaning that it needed good time-to-altitude and top speed. In order to combat the shortcomings of the early jet engines, the XF-91 was fitted with the Reaction Motors XLR11 rocket engine to provide extra thrust. This engine also powered the Bell X-1 through the sound barrier, and the DR-558-II through Mach 2. Due to the obviously limited fuel in the rocket engines and the inefficient jet engine, flight times were extremely limited, topping off at about 25 minutes. This severely limited its usefulness, and was a major reason why the XF-91 never saw production.

One final design quirk about the XF-91 was the variable incidence wing. VI wings are a concept that come up fairly often in prototype aircraft (the XB-51 Tuesday had one as well), but rarely see production due to their complex mechanics and weight. In fact, only one VI plane has ever seen production, the F-8 Crusader of the 1960s. On the XF-91, the VI wing served to lower landing speed while keeping visibility passable.

Ultimately, the XF-91 was passed over for a number of reasons. The short flight time meant that it couldn't effectively patrol airspace, and by the time prototypes were flying, they had been outclassed by the first generation of jet fighters, most prominently the F-86 Sabre.

Download Link:

https://kerbalx.com/servo/XF-91-Thunderceptor

Tomorrow's Craft:

@Munbro Kerman's Lockheed XF-90

 

Edited June 5, 2017 by Servo

[qzgy]

Nice.  notice there are two planes in the image, what's the one on the right? And the back?

[NotAnAimbot]

8 hours ago, qzgy said:

And the back?

The one in the back looks like a XF-88.