Construcciones Aeronáuticas Imperiales CAI-5

[ysi_maniac]

CAI-5

In June 1960, during a long period of truce or cold war in the wars of religion in the Netherlands an English Bristol Britannia, apparently full of passengers, is forced to land in a Catholic airfield after flying for several minutes over resticted areas of Holland and being warned by Spanish fighters. During inspection in ground, it was found that it had no passengers, Britannia was packed with sensors and receivers of all types of radio frequencies. Questioned the crew, it was learned that the flight was dedicated to monitor the response of the Spanish Empire defenses to air intrusions.

The crew was repatriated a few months later but the Britannia is sent to Construcciones Aeronáuticas Imperiales facilities in Madrid. Here two reverse engineering projects are launched, one for the air frame and another for engines.

The first product of this reverse engineering is an almost exact copy of Britannia as airliner, since the Spanish aviation industry so far has only been dedicated to military aircraft. In 1963, Construcciones Aeronáuticas Imperiales presents its new airliner, the CAI-4 (remember the Tupolev-4).

But secretly a derivative of CAI-4 begins to be defined and designed and developed, the CAI-5. It is a combination of VIP and flying command post. The CAI-5 is the response to a request directly issued from the Real Alcazar of Madrid https://en.wikipedia.org/wiki/Royal_Alcazar_of_Madrid .

At that time, Emperor Charles V https://en.wikipedia.org/wiki/Charles_V,_Holy_Roman_Emperor was interested in being able to visit any of its possessions, at any time, on a nonstop flight. Assuming that he will not always have the possibility of being protected by a fighter escort. Thus one of the main requirements is to avoid hostile areas and have some self-protection measures. Naturally it is an airplane equipped with global reach and facilities for flights longer than 24 hours, meeting room, chapel (in the Spanish monarchy the Catholic religion has always had a central role) and command center.

Many configurations were studied:






Draft of requirements:

Range: 20,000 km (3 times the range of Britannia)
Cruise speed: 575 km / h (same as Britannia)
Maximum speed (with booster): 825 km / h

Passive radar
Infrared-guided missiles
Jammers

Can you help me to complete requirements?

EDIT: Decoy dispensers

[FAAMAN]

Wow!!!

[finsrin]

Specially like the top two with jet in tail. :)

[elmayerle]

You are at least going to need an active weather radar and a full range of long-range navigational aids.  If the weather radar happens to have un-advertised additional modes and power, that's all to the good.  I'd probably add ESM and at least at least some protective ECM gear.

[ysi_maniac]

^^^^^ Thanks Evan.
Where can I look for inspiration for this kind of gears in '60s? Prowler? EB-66? A-1E/AD-5?
Can you give me examples of pods?

[elmayerle]

Let me get back to you on that.  I'm a bit off today after getting both flu and shingles shots (the perils of getting older - still beats not making it, though).  A-1E might have something, also look at what Wild Weasel I aircraft carried.  For IRCM, I doubt the technology of the time would allow much beyond flares but you use what you have.  You want to have some fun, fit copied versions of the RAF's standard RHAWS to the vertical tail with secondary installations on the wing tips.  If you wanted to be sneaky, bulge the lower cargo/baggage bay doors just slightly, make them from radio-wave transparent fiberglass (same material as radomes), and mount ELINT/ESM antennas (shows how Latin still affects me, I keep wanting to write that plural as "antennae") behind them where they wouldn't be immediately obvious or noticed.

[ysi_maniac]

Radomes à la EC-121H? smaller maybe.

[elmayerle]

Radomes à la EC-121H? smaller maybe.

For an AWACS-type usage, that would work.  For covert ELINT, SIGINT, COMINT, et al.  you don't want something too noticeable.  Now, if I wanted a VIP transport with some self-protection capabilities, I'd have the forward cargo/baggage bay doors replaced be radomes and radars to help supplement the "enhanced" "weather radar" in the nose with the aft doors set up to allow quite deployment and firing of IR missiles, SARM missiles if the radar had the capability.

[ysi_maniac]

Ok, Evan.
Now, let's speak about global range. It would need huge tankage. Would baggage bay have enough room? Perhaps external tanks fitted only when needed?

[elmayerle]

I don't know that the baggage/cargo hold would have enough room, particularly if there were specialized electronics down there.  I'm probably use all the space I could for fuel and then add underwing drop tanks, as on the later-model B-50s, when extra range was needed.

[ysi_maniac]

Current design is in this state:

[The Big Gimper]

Very good work Carlos.

[ysi_maniac]

I began construction with Britannia 4 propellers config in mind. Then wings looked too masive to me ...


So I considered a 2 props config, deleting inner section of wing and out engines. This was realized as follows: inner section and inner engine was deleted but inner gondola was kept in order to switch it for the other gondola. The point was that uc is carried on inner gondola. Then a 4 meter section was added to wing tip.


Here styrene version



Deleted parts

[ysi_maniac]

Cockpit area.




Tail fin. You can see retractable air intake for tail turbojet:


Tail fin design will be inspired by an obscure but attractive Tupolev project: Tu-101

[Jeffry Fontaine]

Looking good Carlos! 

[Brian da Basher]

That's a truly inspired combination and I'm glad to see you back at this one.

Brian da Basher

[Camthalion]

Looking good