Your Nation's Air Force Mark III: Best Korea Edition

[Austrasien]

You know NS isn't real, right?

Things could not have been produced by God in any other way or in any other order than is the case

[New Vihenia]

Someone pls remind me on why we dont have Airborne carrier with parasite fighter squadron inside it ?

[The Manticoran Empire]

Someone pls remind me on why we dont have Airborne carrier with parasite fighter squadron inside it ?

Because ocean going carriers and airbases are more efficient.

[The Corparation]

Someone pls remind me on why we dont have Airborne carrier with parasite fighter squadron inside it ?

Because ocean going carriers and airbases are more efficient.

And also because air to air refueling is cheaper, easier, and frees the fighter from the constraint of having to fit inside another plane.

[Nou Pais Valencia]

My country wasn't very afluent or industrialised untill the 1960s and hit hard by the 1970s oil crisis that affected my country's Air Force expansion and hability of maintain it's capacities. Also until recently there was little aeronautic industry able to produce aircraft. Valencian manufacturers mostly built light transports and liason and training aircraft.

The FAPV or VCAF in English since in became and independent air force in 1948. It has used a mix of Western European (mostly French) and US made aircraft. For example The army Air Force received in the years previous to WWII as tensions rose in Europe 30 Gloster Gladiator, 30 caproni CA-310 and 30 Ju86 bombers as war was progresing it obtained 18 Supermarine Spitfire as those were getting outdated and some interned belligerant aircrafts. From 1943 to drive the País Valencià to "collaborate" with the Allies it received 93 Spitfires MKVCs among other models as some B25s. With the War's end it received 50 Surplus P47D from the USA, 30 T6D and some B26 and C47 from US stocks in Europe. The P47 remained in service until 1957 during the 50s it got 50 F86F as US military asistance and 24 Supermystere from Dassault and F5A/B and Mirage III in the 60s and F5E/F in the 70s in the 80s it got second hand Mirage Vs.

Currently it operates Mirage 2000-5s and F16C/D block 52, M346 trainers, T6 texans II and C130J and C27J for example.

[The Akasha Colony]

If a modern replacement to KH-9 Hexagon with similar wide-area surveillance capabilities were to be developed, would conventional film still be required?

Given the tremendous data bandwidth, storage volumes, and power required to handle such data digitally, I imagine that a film setup might still be simpler and a faster way to downlink the data (with little chance of jamming or cyberattack). But the cost of more advanced modern optics would also increase the preference toward extended endurance over the four or five return capsules KH-9 carried.

Improvements in computer analysis seems to have advanced enough to make processing such large volumes of imagery reasonably feasible on a more regular and ongoing basis which would also encourage more regular use which might also encourage the development of a more reusable digital solution.

Perhaps a better solution might be to use a larger number of smaller satellites each with more limited coverage but also needing less bandwidth and storage to operate?

[The Manticoran Empire]

If a modern replacement to KH-9 Hexagon with similar wide-area surveillance capabilities were to be developed, would conventional film still be required?

Given the tremendous data bandwidth, storage volumes, and power required to handle such data digitally, I imagine that a film setup might still be simpler and a faster way to downlink the data (with little chance of jamming or cyberattack). But the cost of more advanced modern optics would also increase the preference toward extended endurance over the four or five return capsules KH-9 carried.

Improvements in computer analysis seems to have advanced enough to make processing such large volumes of imagery reasonably feasible on a more regular and ongoing basis which would also encourage more regular use which might also encourage the development of a more reusable digital solution.

Perhaps a better solution might be to use a larger number of smaller satellites each with more limited coverage but also needing less bandwidth and storage to operate?

I don't know. Possibly. My concern would be interception or failure of the return capsules. I think that a way to get around the interception issue would be to have the download occur over friendly territory, whether using capsules or digital download. The digital one will probably be what any 21st century KH-9 uses, simply for reasons of economy.

[Roskian Federation]

If a modern replacement to KH-9 Hexagon with similar wide-area surveillance capabilities were to be developed, would conventional film still be required?

Given the tremendous data bandwidth, storage volumes, and power required to handle such data digitally, I imagine that a film setup might still be simpler and a faster way to downlink the data (with little chance of jamming or cyberattack). But the cost of more advanced modern optics would also increase the preference toward extended endurance over the four or five return capsules KH-9 carried.

Improvements in computer analysis seems to have advanced enough to make processing such large volumes of imagery reasonably feasible on a more regular and ongoing basis which would also encourage more regular use which might also encourage the development of a more reusable digital solution.

Perhaps a better solution might be to use a larger number of smaller satellites each with more limited coverage but also needing less bandwidth and storage to operate?

I'm pretty sure that this could be processed via digital solutions, such as like hundred+ terabyte hard drives. I don't think film would be required at all if im entirely honest.

[New Vihenia]

If a modern replacement to KH-9 Hexagon with similar wide-area surveillance capabilities were to be developed, would conventional film still be required?

Given the tremendous data bandwidth, storage volumes, and power required to handle such data digitally, I imagine that a film setup might still be simpler and a faster way to downlink the data (with little chance of jamming or cyberattack). But the cost of more advanced modern optics would also increase the preference toward extended endurance over the four or five return capsules KH-9 carried.

Improvements in computer analysis seems to have advanced enough to make processing such large volumes of imagery reasonably feasible on a more regular and ongoing basis which would also encourage more regular use which might also encourage the development of a more reusable digital solution.

Perhaps a better solution might be to use a larger number of smaller satellites each with more limited coverage but also needing less bandwidth and storage to operate?

Or make re-usable the whole satellite down a.l.a Soviet era early Zenit. Tho for large diameter optics i can see the whole assembly is going to be quite large.

[The Akasha Colony]

My concern would be interception or failure of the return capsules. I think that a way to get around the interception issue would be to have the download occur over friendly territory, whether using capsules or digital download.

This is how it was done historically. It certainly wasn't done over enemy territory. Capsule failure was not a common problem since the capsules themselves are quite simple.

The digital one will probably be what any 21st century KH-9 uses, simply for reasons of economy.

Economy is a tricky thing.

Matching the sheer data-collecting capability of the film system developed by Perkin Elmer for KH-9 would require developing an onboard digital storage system capable of processing and storing hundreds of gigabytes per second just to match Hexagon's capabilities and it would need an onboard array of many tens (if not the low hundreds) of terabytes of storage. The storage requirement on its own isn't much of a problem as modern solid state memory is extremely compact and relatively inexpensive but the processing and writing speed would pose a challenge, as could the power and cooling requirements. Not an insurmountable one but one that would certainly drive up the cost of a digital system.

This is before considering downlink times. A dedicated high-bandwidth communications satellite like ViaSat-2 can manage a few hundred Gbits/sec. Using the entire rated bandwidth of ViaSat-2 would require over 22 hours to downlink 50 TB of data.

And this assumes the goal is merely to equal KH-9. Improving on KH-9 with a higher resolution would generate commensurately more data although it would also require a commensurately large optical bar anyway.

I'm pretty sure that this could be processed via digital solutions, such as like hundred+ terabyte hard drives. I don't think film would be required at all if im entirely honest.

Digital solutions could do it quite easily. On Earth.

They could do it in space too, but there are a number of additional challenges. Spinning hard drives are more or less out as they simply don't have the bandwidth to handle the immense write speeds required to store the data in real time. They are also vulnerable to mechanical failure which is undesirable in a multi-billion dollar satellite. Storage requirements could be reduced by using lossy or compressed storage formats but this would require an increase in computing power to handle the compression in real time.

The challenge is not unlike the one faced by research institutions when collecting data from high-energy physics experiments. On the one hand, a satellite would likely generate less data on an ongoing basis than something like the LHC (which generates dozens of petabytes of data per year) but on the other hand these institutions can rely on landline connections to affiliated institutions to help bear the load. A satellite would have to operate independently.

Or make re-usable the whole satellite down a.l.a Soviet era early Zenit. Tho for large diameter optics i can see the whole assembly is going to be quite large.

Yeah, even if you lopped off the film return capsule section of KH-9 you still have a body nearly 8 meters long and 3 meters wide. You'd probably need something like a space shuttle to pick it up and return it to Earth as it is almost certainly too big for an independent parachute-arrested landing.

[Danternoust]

Not an insurmountable one but one that would certainly drive up the cost of a digital system.

https://en.wikipedia.org/wiki/North_American_X-15
https://en.wikipedia.org/wiki/Sr-71

If you can afford a spy satellite, you can afford this.

It isn't required to mimic your nation's broken procurement process.

[Special Aromas]

If a modern replacement to KH-9 Hexagon with similar wide-area surveillance capabilities were to be developed, would conventional film still be required?

Given the tremendous data bandwidth, storage volumes, and power required to handle such data digitally, I imagine that a film setup might still be simpler and a faster way to downlink the data (with little chance of jamming or cyberattack). But the cost of more advanced modern optics would also increase the preference toward extended endurance over the four or five return capsules KH-9 carried.

Improvements in computer analysis seems to have advanced enough to make processing such large volumes of imagery reasonably feasible on a more regular and ongoing basis which would also encourage more regular use which might also encourage the development of a more reusable digital solution.

Perhaps a better solution might be to use a larger number of smaller satellites each with more limited coverage but also needing less bandwidth and storage to operate?

Correct.

The question is whether you need the 40,000km2 photos available every five days or whether 1,000km2 imagery transmitted in real time are more useful to you. The NRO & CIA decided that real-time image availability was more important and KH-9 became the last US film satellite program.

KH-11 transmits data at a frequency too high to pass through the atmosphere and instead uses a relay system of other satellites before transmitting back to earth, which keeps the probability of intercept fairly low. It's also doubtful it stores any data on-board as it's unnecessary with a full-time data link.

[Danternoust]

40,000km2 photos available every five days or whether 1,000km2 imagery

So, you're saying we can have very accurate photos, more accurate than Google Maps, which mostly uses imagery from planes?

[New Vihenia]

is 8 meter diameter mirror practical for spy satellite ?

Apparently for 0.1 m resolution from 750 km at visible light wavelength. That's the required size. But i guess we dont really have rocket that big yet. except the unbuilt Energia-Vulkan.

[Danternoust]

is 8 meter diameter mirror practical for spy satellite ?

Apparently for 0.1 m resolution from 750 km at visible light wavelength. That's the required size. But i guess we dont really have rocket that big yet. except the unbuilt Energia-Vulkan.

https://en.wikipedia.org/wiki/Wet_workshop
https://en.wikipedia.org/wiki/S-II

No, it is possible.

[The Technocratic Syndicalists]

If a modern replacement to KH-9 Hexagon with similar wide-area surveillance capabilities were to be developed, would conventional film still be required?

Given the tremendous data bandwidth, storage volumes, and power required to handle such data digitally, I imagine that a film setup might still be simpler and a faster way to downlink the data (with little chance of jamming or cyberattack). But the cost of more advanced modern optics would also increase the preference toward extended endurance over the four or five return capsules KH-9 carried.

Improvements in computer analysis seems to have advanced enough to make processing such large volumes of imagery reasonably feasible on a more regular and ongoing basis which would also encourage more regular use which might also encourage the development of a more reusable digital solution.

Perhaps a better solution might be to use a larger number of smaller satellites each with more limited coverage but also needing less bandwidth and storage to operate?

Yes. No digital telescope can match the resolution and field of view of an OBC.

One solution would be to put the OBC in an X-37 type vehicle which can be launched and recovered as needed.

[Gallia-]

Boeing Surveillance Robot Model 72.

[The Akasha Colony]

https://en.wikipedia.org/wiki/North_American_X-15
https://en.wikipedia.org/wiki/Sr-71

If you can afford a spy satellite, you can afford this.

Neither of these things do anything resembling what KH-9 did. SR-71 generally didn't overfly the Soviet Union and was restricted to looking in from along the border. And regardless of speed, the political matter of flying over someone's territory for surveillance purposes without permission is a rather troublesome thing which satellites avoid.

This isn't to say that there isn't a use for surveillance aircraft, but it is rather obvious that they are not the sole solution to the surveillance question.

It isn't required to mimic your nation's broken procurement process.

The cost of a digital system vs. a film system has nothing to do with the procurement process. It is simply a matter of dealing with the inherent challenges in regards to data processing, storage, and transmission. Developing a system that can handle hundreds of gigabytes per second of writes isn't too hard; big data centers do it all the time. But doing it on a satellite with limited volume, power, and cooling, and with enough reliability to operate for a decade at a time with no physical maintenance is not an inexpensive proposition.

Correct.

The question is whether you need the 40,000km2 photos available every five days or whether 1,000km2 imagery transmitted in real time are more useful to you. The NRO & CIA decided that real-time image availability was more important and KH-9 became the last US film satellite program.

KH-11 transmits data at a frequency too high to pass through the atmosphere and instead uses a relay system of other satellites before transmitting back to earth, which keeps the probability of intercept fairly low. It's also doubtful it stores any data on-board as it's unnecessary with a full-time data link.

I wouldn't consider it an "either-or" situation, since the concept was to use KH-11-like point surveillance satellites supplemented by a few KH-9-like wide-area satellites which would also be used for general mapping purposes. Although perhaps the mapping mission could be spun off into another satellite with lower resolution and a digital processing system to handle the needs of an ongoing mapping mission more economically than a film system.

I figured an onboard caching system for collected imagery would be more practical in this instance than trying to develop a datalink that could handle the data stream in real-time.

So, you're saying we can have very accurate photos, more accurate than Google Maps, which mostly uses imagery from planes?

Resolution is a matter of mirror size. If you know the primary mirror size you can calculate the upper bound of the optical resolution for a given telescope. KH-11 originally had a mirror diameter of 2.4 meters (the same as Hubble) but there are claims that newer KH-11s have 3 meter primaries. IIRC the suspected resolution of KH-11 is around 0.15-0.2 meters. The actual operational resolution is impossible to determine without knowledge of the actual hardware and will vary based on atmospheric turbulence.

Also, Google Maps uses aerial imagery only for high-interest, high-density areas like cities and other major points of interest. For most of the world's flyover territory it uses satellite imaging which is far cheaper. But that's irrelevant here because generally most nations that are subject to surveillance are not fond of surveillance aircraft flying 200-400 meters above potentially sensitive military/industrial installations.

is 8 meter diameter mirror practical for spy satellite ?

Apparently for 0.1 m resolution from 750 km at visible light wavelength. That's the required size. But i guess we dont really have rocket that big yet. except the unbuilt Energia-Vulkan.

There's no reason an 8+ meter payload fairing couldn't be built. AFAIK the Ares V derivative of SLS was going to have a payload fairing of roughly that size.

Yes. No digital telescope can match the resolution and field of view of an OBC.

One solution would be to put the OBC in an X-37 type vehicle which can be launched and recovered as needed.

Ah, that would be an interesting solution. Although it would make it more obvious whenever a surveillance mission is being conducted.

[Gallia-]

CaLV the secret plot to deploy Zenith Stars to lock down low orbit from ASAT weapons

origami battle stations have met their match

[Danternoust]

My nation's navy and air force is one-fuel, hydrogen. I suppose this might reduce aircraft range more than the naval ships, but it won't be that bad, would it?

[The Manticoran Empire]

My nation's navy and air force is one-fuel, hydrogen. I suppose this might reduce aircraft range more than the naval ships, but it won't be that bad, would it?

It will have reduced takeoff weight, due to hydrogen being lighter than air. However, the nature of hydrogen requires that it be stored in the fuselage, requiring a longer fuselage that results in a loss in performance. I would say just stick with normal aviation fuel.

[Gallia-]

My nation's navy and air force is one-fuel, hydrogen. I suppose this might reduce aircraft range more than the naval ships, but it won't be that bad, would it?

Yes it would be terrible.

[Danternoust]

My nation's navy and air force is one-fuel, hydrogen. I suppose this might reduce aircraft range more than the naval ships, but it won't be that bad, would it?

It will have reduced takeoff weight, due to hydrogen being lighter than air. However, the nature of hydrogen requires that it be stored in the fuselage, requiring a longer fuselage that results in a loss in performance. I would say just stick with normal aviation fuel.

Hmm. I'll need to use a flying wing design.

Maybe hydrogen will only be used for crafts that require complex logistical support to begin with, to merit the construction of hydrolysis facilities. Can't find information on the performance loss of hydrogen versus kerosene though, so maybe it is a 60% loss in range. Would only be good for high-altitude interceptors or surveillance craft then.

Fig. 20. High-altitude, subsonic reconnaissance airplane using liquid hydrogen as fuel. The liquid hydrogen tanks are in both fuselage and wings. Flight Mach number, 0.75; altitude 24400 m. From Silverstein and Hall, "Liquid Hydrogen as a Jet Fuel," 1955.
Source: https://history.nasa.gov/SP-4404/ch6-3.htm

[Kassaran]

The image of his craft exploding comes to mind at the first attempt of me lighting a match within 100 feet. Don't even want to consider what proximity missile fragmentation would do.

[The Akasha Colony]

My nation's navy and air force is one-fuel, hydrogen. I suppose this might reduce aircraft range more than the naval ships, but it won't be that bad, would it?

Hydrogen and kerosene have tremendously different operational characteristics.

It would be like converting your entire army to run on charcoal.

Strangely enough there are very good reasons why IRL navies and air forces don't run on hydrogen.