The Century Series - A story of innovation and improvement

[Servo]

The Century Series

A dual story of progress and creation

The Century Series before the introduction of the F-106 in 1959.

Clockwise from upper right, F-105 Thunderchief, F-101 Voodoo, F-102 Delta Dagger, F-100 Super Sabre, and F-104 Starfighter

In the early 1950s, the U.S. aircraft manufacturers had taken the lessons learned from the first generation of jet fighters into account when designing a new suite of aircraft for the modern air war. These planes would keep pace with the rapidly advancing technologies of the time, with powerful engines, radars, afterburners, and complex fire-control systems coming into their own for the first time.

The North American F-100 Super Sabre was the first U.S. Jet capable of level supersonic flight

The second generation of jet fighters for the newly minted United States Air Force would take the naming convention used by the previous subsonic fighters to a new level. The F-100 Super Sabre led off the now-iconic Century Series, which ultimately saw the addition of five other aircraft. Other aircraft shared the naming series, but only the ones discussed here saw any production beyond the prototype phase. They entered service at a key time for the USAF, fighter command as it was expanding its role and reach to include more roles - peacetime interception of enemy bomber patrols, reconnaissance overflights of key targets, and tactical strikes made by fighter aircraft instead of lumbering bombers.

The McDonnell RF-101 Voodoo was a reconnaissance platform which made key low-level overflights of missile sites during the Cuban Missile Crisis

Another key development during this time period was the development of the doctrine of air-to-air refueling. The Century Series were the first planes equipped to take on fuel during flight, a technology which extended both operational ranges and mission durations, while also increasing mission readiness. This air-to-air refueling was used for a novel purpose in October of 1957, when during Operation Sun Run, a trio of stripped-down RF-101 Voodoos took off from Los Angeles and over the course of the next seven hours flew to New York and back, after a total of 25 air-to-air refuelings across the fleet.

The Convair F-102 Delta Dagger was delayed three years due to difficulties in understanding the aerodynamics of transonic flight

These new technologies weren't without their troubles, though. The aerodynamics of supersonic and transonic flight were poorly understood in the 1950's. The design of the experimental aircraft which broke the sound barrier were modeled off of 50 caliber bullets, since that shape was the only one known to be stable at supersonic speeds. Early supersonic planes such as the F-101 and the F-100 dealt with the problem of aerodynamics mainly through experimentation rather than theory, and relied on relatively thin wings and perhaps good fortune on the part of the designers. However, when the first F-102 prototype took to the skies, they realized that something was wrong with the design. The supposed Mach 1.5 interceptor couldn't even go supersonic - and it wasn't entirely the engine's fault. Extensive research led to the rediscovery of the Whitcomb Area Rule, the guiding rule for transonic drag on aircraft, and its implementation on the F-102 allowing it to reach much higher speeds. This is responsible for the shock bodies seen on the engine nozzle (modeled here by the landing gear), as well as the characteristic wasp-waist of many of this era's fighters. It is most noticeable on the F-102 and F-106, but it is present on the F-105 as well.

The Lockheed F-104 Starfighter looked like something out of fiction, but soon helped turn spaceflight into science fact

In the 1950s, as the space race heated up, both the Soviet Union and the United States began looking for candidates to fill the ranks of their astronaut corps. Both found a natural fit in their highly-trained jet fighter pilots, and particularly the subset of test pilots. This would be enough to cement the relationship between the Starfighter and the first spacecraft, but the F-104 had another unique contribution to the space program. The U.S. Air force needed to train its prospective astronauts to navigate out of atmosphere, using RCS thrusters instead of control surfaces, but had no good way of testing the systems in a full-system way. They tapped Kelly Johnson of Skunkworks to develop a testbed for the new technology, and in 1963, the NF-104A made its first flight. This was a modified starfighter equipped with rocket engines to boost the maximum altitude of the F-104 from 50,000 feet to 120,000 feet in high arcing climbs during which the aerodynamic control surfaces of the fighter would become useless and the pilot would use the RCS system to maneuver instead. This testbed worked, and the technology was proven for use in manned spaceflight.

The Republic F-105 Thunderchief was a victim of a changing air war, saved only by the development of the SEAD role for the platform

Introduced too late for the war in Korea, the first real tests of the series came in the skies over Vietnam. They soon discovered that air war had changed, and not in a way that favored the jet fighter. The proliferation of radar-directed fire control, nimble and hard to hit enemy MiGs, and the newly-proven surface-to-air missile led to loss rates far higher than any in the USAF upper echelons expected. Hit hardest by this changing battlefield was Republic's F-105 Thunderchief. True to its spiritual ancestor, the P-47 Thunderbolt, Republics newest jet fighter was the heaviest single-engine, single-seat fighter ever built. It was designed to carry bomb loads heavier and faster than a B-17, get in, and get out alive. However, the world of agile fighters,and accurate AA fire firing more powerful munitions meant that being tough wasn't a ticket to survivability any more. The F-105 ultimately became the only U.S. aircraft pulled from frontline fighting due to heavy loss rates, and would have been deemed a complete failure were it not for the development of the Suppression of Enemy Air Defenses (SEAD) team. SEADs squadrons, better known as Wild Weasel squadrons, flew the EF-105, which carried advanced electronics monitering and tracking systems, as well as radar-seeking missiles. They would fly ahead of the strike team into defended air space and bait the enemy radar installations into attempting to lock onto their aircraft. Then, they would track the radar signal and direct guided weapons to destroy the air defenses. Fitting for a squadron whose main job is playing chicken with SAMs, their slogan was "You've got to be (screwing)  me", reportedly said by the Captain when he was first tole what his mission would be. The Wild Weasel squadrons live on today, now flying highly modified EA-18 Growler.

The Convair F-106 Delta Dart was the last dedicated interceptor fielded by the U.S.A.F, showing a shift in the roles of fighters in the Air Force

The Century Series tells the story of a developing air force, and a consolidation of the roles played by its fighters. The F-100, F-101A, and F-105 were fighter-bombers which were designed to tangle with enemy fighters and ground units, while the F-101B, F-102, F-104, and F-106 were dedicated straight-line interceptors designed to get somewhere as fast as possible and take out enemy bomber formations. This dichotomy was a holdover from the days of WWII when a variety of aircraft filled different roles. However, the consolidation of the aircraft industry (it took a large company to enter the jet market, so many mergers occurred and smaller companies exited the market) and the rise of the multi-role fighter ended the lines of the dedicated interceptor and the dedicated fighter-bomber. This is immediately evidenced by the fact that in the U.S., only a single plane is considered a Third Generation fighter (the Century Series, among others, make up the Second Generation): The F-4 Phantom II. The fact that a single aircraft could be used across the USAF, USNAF, and USMC in all manner of roles was revolutionary at the time, and echoes the consolidation present today with the Joint Strike Fighter.

The Century Series represented a period of extreme technological growth and progress from the fledgling USAF

As with the USAF, the Century Series has been a metric of progress for myself as I continue to push the boundaries of what's possible with stock parts

My first act as a stock replica builder, three years ago yesterday, was to upload the entirety of the Century Series to KerbalX. They were fair replicas, nothing extremely fancy, but they were recognizable and set the stage for the years to come (at least for me). But I take a lot of pride in these first steps, since they show the seeds of what the future held in store, both for myself and the rest of us stock replica builders. 

There is a lot of growth that came between these two screenshots, but what is more interesting is what stayed the same. 

Larger than expected replicas, allowing for more detail

Strange use of parts - airbrakes, parachutes, and communotrons are used to get colors and shapes right

Using the craft to tell a story - the early series were the first planes I built in my Jet of the Day series

As we move forwards into a new decade, remember to look back and reflect on how far you've come, and just think how much farther you have left to climb. Here's to a good 2020

-Servo

Edited January 1, 2020 by Servo

[Vanamonde]

The Supersabre has always been one of my favorite planes. It's just the quintessential jet shape. 

[Servo]

7 hours ago, Vanamonde said:

The Supersabre has always been one of my favorite planes. It's just the quintessential jet shape. 

Oh I love it so. 

My F-100 replica was a major step forwards for me in terms of build quality and techniques. I think I'll take the next few days going deep on the build techniques I used to create each of these craft, one day at a time. 

This F-100 was the result of my embracing the power of the Mk0 tank as a fuselage shaping tool. I had used it somewhat in my earlier F/A-18 and Dassault Rafale, but the use in those builds was either more limited or less effective, primarily due to the lack of an effective way of filling in the sides of the fuselage. Thanks to the mostly flat sides of the Super Sabre. There are also several notable uses of landing gear as structural elements rather than functional elements. Landing gear came into their own in early 2018. My memory fails me, but I know that @NorthAmericanAviation had been using landing gear as nose cones since before then, but the earliest use (and likely where I found the technique) of landing gear as something other than a nose cone was @EvenFlow's F-15 in March. Landing gear have a very unique shape which lends them to replicating curved and organic shapes (the latter shown by @EpicSpaceTroll139's Dinosaurs), making them perfect for the tapered bits at the nose.

Two other techniques are on full display here, each of which I either developed or perfected in this craft. The most distinctive element of the F-100 (and the one which has vexed so many craft-builders for so long) is the ovular intake on the nose. The use of the communotron here was a flash of insight that I can only attribute to my time spent building small-scale craft (another proof that spending time doing something other than your main thing can lead to new insights). The communotron is a perfect part to use when shaping intakes of all kinds, and it's singlehandedly added 50 parts to every craft that I've made since then. Communotrons are also on display here. For a beautiful example of the sort of work that you can do with communotrons, @Kronus_Aerospace has a beautiful F-104 with intakes painstakingly crafted from communotrons.

The second thing here that's present is the Oscar-B tank cockpit. This is EvenFlow's great contribution to stock replica builders everywhere. They're controversial (every time I post a Oscar-B cockpitted plane, there are always comments), but I really do enjoy their sleek look, ease of construction, and and relatively low part count compared to comparable solar panel or gravioli methods). 

Now, for the old one. Honestly, this one's not as bad as I remembered it. KSP aero updates have actually been rather kind to this little jet. Similarly, my appreciation for this odd little plane's build quality has grown as it aged. It's got a bit of the Mk0 tank work going on on the spine, and even more importantly, there's a gem that I hadn't remembered: the communotron spike on the tail. Seems like I always return back to some things after all. Even the fuselage has its charm - the Radial Ramp intakes create a decent impression of the shaping of the nose, and the Mk0 intakes, while awkward, are about par for the course as far as Super Sabre intakes go.

Another fun note that isn't on display as much in the modern F-100 as in my other modern replicas: the stripe on the fuselage continues across multiple parts. Edge alignment is a key element of my modern attempts at "smooth" building (a good example of which is my F/A-18 Hornet, reference the fuselage side.) Perhaps I'll discuss that more as I take a look at the F-101 Voodoo next.

This has been a really fun exercise in reflection and analysis for my own purposes, so I hope you enjoy reading it! I'll be back soon with a look at some of the other planes featured here.

 

 

[Servo]

The McDonnell RF-101 Voodoo

The RF-101C of the NMUSAF, which took part in Operation Sun Run, the fastest transcontinental flight of its time.

This will focus on my replica of the RF-101 reconnaissance variant, rather than the fighter-bomber and interceptor variants (F-101A/C and F-101B, respectively). When I was just a wee lad, my grandfather gave me a book featuring photos and writeups of every aircraft in the National Museum of the U.S. Air Force. Included in the book was the above image, and something about it must have stuck in my mind, since when I began building my first pass at the Century Series, I made sure to build the recon variant rather than any of the other ones. Something about the odd nose shape appealed to me, so I wanted to make sure it was replicated.

Here's the result of that little bit of inspiration. This plane has some interesting things going on here, particularly in the nose. The shape of the camera-holding schnozz required the use of long-flat pieces, which resulted in my using the backs of radial ramp intakes, a technique which would come back several times on my builds (including on the undersides of my modern F-100 and F-101 builds). If you need a long, flat section (or one with a slight camber), flipping them works really well. Doubly so if you need the colors to match with wings, or they just need to be a constant color. 

Moving upwards, the black area is created using the undersides of communotrons was a new thing as near as I can tell. I have no idea why I did it (the color wasn't the reason, so I guess it must have been the shape), but it's a technique that would return often. Pics below:

Spoiler

Here it is on my P-51 Mustang. Amusingly, after I released this one, it seems a lot of other WWII replica builders took this technique and ran with it.

For more examples,

@HolidayTheLeek's Ki-84 https://kerbalx.com/HolidayTheLeek/AC-Ki-84-Hayate. The cockpit on this one is super cool, plus the propeller hub looks awesome.

@Phantomic's lovely F-82 Twin Mustang: https://kerbalx.com/PhantomAerospace/F-82-Twin-Mustang. This one's another great example of the power of the backside of ramp intakes.

 

These builds provide another interesting example of cross-pollination between replica builders - the cockpits on both mustangs appear very similar, but that's because they were built using the same technique, pioneered by HolidayTheLeek.

 

 

My RF-101C: https://kerbalx.com/servo/RF-101C-Voodoo

As promised previously, this plane is a great example of how edge alignment can make a build look smoother than it really is. If nothing else, it makes it look like you put a lot of time into perfecting how your craft will look, which is a good thing. The later craft in the series are all good examples of this too, but since this craft has the most different things going on to align, I figured that I'd go for it here. Plus, I'm impatient.

This technique relies on the fact that the structural fusealges, structural wings, and doubled Mk0 tanks are all the same length, meaning that you can create repeating patterns. This means that more of the surface is flat textures, pushing towards the idea of "smooth" crafts. More on that below:

Spoiler

"smooth" is hard to define, but hopefully this example helps. Both are built by @ScaryTerry, who is a criminally underrated builder.

Smooth craft - it's hart to pick out exactly what parts are used where, and where boundaries between parts are. The greatest compliment you can get about this is "I swore it had to be modded."

https://kerbalx.com/ScaryTerry/Orca-Assault-Craft

And a less-smooth craft. This is an earlier build of Terry's, and the progression of skill is very impressive, especially given how quickly it's happening.

Angles are jarring, part colors change awkwardly, and some parts have seams or discontinuities (especially with the fairing base and the cockpit)

https://kerbalx.com/ScaryTerry/Hawker-Hunter-F6

Another useful lesson learned from this craft is the use of varied color palettes. This area is what I hope to make an impact in for other builders - using different sets of parts in a continuous fashion to create different colors. I went into a lot more depth here:

Or, in short:

Light: White fairings, radiators (static)

Standard: Jet fuel tanks/Structural fuselages, wings, airbrakes, landing gear, ladders, solar panels (stowable), Inline Clamp-o-trons, air intakes, backs of radial air intakes. RCS balls. The rectangular prism probe core.

Blue: Solar panels, gravioli detectors - warning: they are not the same color blue

Dark Grey/Back: Backs of small fuel cells, backs of deployable communatrons, ore tanks

Medium Grey: Large Fuel Cell backs, solar panel backs, I-beams, atmospheric spectro-variometer backs, structural panels. Small LFO tanks. Thermometer backs.

 

This craft has a couple different palettes in different areas, featuring the black palette on the nose to create the film windows, standard palette on the fuselage and wings, and the medium grey forming the cockpit and engine area. If I were less aggressive about part count, I would have differentiated the cockpit and engines by using a bluer parts on the cockpit.