Large scale colonization ship

RobertDyck · 2020-09-13 14:00:01

kbd512 wrote:

The entire point I was trying to make, which was clearly lost in the argument, was that the passengers were going to have to function as the bulk of the crew members for the ship, specifically because there would be so few assigned crew.

Good idea

kbd512 wrote:

If you have cargo handlers who have hand-to-hand combat skills and have been given authority to act as law enforcement, after appropriate training and testing, then you could use them for that purpose.

Yes. When I was a clerk for 7-Eleven, I ran the store alone for the overnight shift (graveyard shift). I had to face down shop lifters. They backed down. And no one tried to rob my store while I was on duty. Earlier this year I saw criminals walk out with arms full of booze bottles. Store security had a uniform but didn't even try to stop the criminals. I thought I did a better job when I was a clerk, and he's supposed to be dedicated security.

tahanson43206 · 2020-09-15 09:46:09

This is an update to the model of a Circle Y ship design.

The dimensions of the RobertDyck Circle Y design include specification of a rim diameter of 76 meters. (Mars gravity at 3 RPM)

The proportions have been corrected so the "handle" is at a ratio of 1:161 to the rim diameter.

As a reminder, a YouTube video of the rotation of an earlier model (with a short "handle") is available:

https://www.youtube.com/watch?v=UyyPf8U5p2g

(th)

RobertDyck · 2020-09-18 14:22:03

I'll work out an estimate of vehicle mass; ring, spokes, hub. Not sure how large the zero-G cargo hold should be. When we have a rough mass estimate, together with main engine Isp we can.calculate propellant. That will give us required tank volume. You suggested Sam tank diameter as Starship. Ok, this will give us length

Ps. Detailed calculation will allow us to compare aerocapture vs propulsive orbital insertion.

RobertDyck · 2020-09-20 00:23:32

Example of hull from Wikipedia: Multi-Purpose Logistics Module (MPLM)

Length – 6.6 m (cylindrical part 4.8 m)
Width – 4.57 m
Mass – 4,082 kg empty; 13,154 kg fully loaded
Habitable volume – 31 m3
Material – stainless steel

cylinder
4.57m diameter x 4.8m long, circumference = Pi x 4.57m = 14.357m
area = circumference x length = 68.913976449145704478916545255619m²

Wikipedia: Common Berthing Mechanism

Length ~16 in (0.4 m)
Diameter ~71 in (1.8 m)
Active CBM (Type I)
Mass 540 lb (240 kg) (specified)

mass without CBM hatch = 4,082kg - 240kg = 3,842kg

total length 6.6m - cylinder / 2 = 0.9m each cone
truncated cone surface area = 16.527204523019666m²

back end disk area: 1.8m diameter. area = Pi * R² = 2.5446900494077325231547411404564m²

total hull area = cylinder + both cones + disk = 68.913976449145704478916545255619m² + 16.527204523019666m² x 2 + 2.5446900494077325231547411404564m² = 104.51307554459276900207128639608m²

mass per square metre of hull: 3,842kg / 104.51307554459276900207128639608m² = 36.760950531598579018448795991648 kg/m²
round to 36.76 kg/m²

Ring radius to surface of floor: 37.6992m
Thickness of floor (guess): 5mm
SPACE STATION MMOD SHIELDING
Typical ISS MMOD shield: 2mm Al outer hull, MLI, Nextel, Kevlar, 4.8mm Al inner hull. Total thickness 11cm.
This is with an aluminum instead of stainless steel, but let's use 11.5cm total for hull thickness from surface of floor.

If someone wants to argue for aluminum alloy pressure hull like Discovery instead of stainless steel like Leonardo, then could you give me mass and dimensions of the hull without equipment or fittings?

So ring side wall is disk area subtract disk that isn't there.
Outside radius 37.6992 + 0.115 = 37.8142m
Inside radius 37.6992 - 2.4 - 0.115 = 35.1842m
(2.4 metres = 7 foot, 10.488 inches. And this accounts for 5mm thick ceiling treatment.)
Pi x R² (outer) - Pi x R² (inner) = 603.14m² (each side)

Floor hull: Pi x D where D is 2 x outside radius = circumference
Ring width is 19m + forward hull + wall panel against forward metal hull + aft hull + stand alone wall panel.
But the aft wall has a water reservoir / water wall. 10.2cm (4.01575") thick water tank. Wall panel will be 1cm thick to hold in water bladder.
Ring width is 19m + 0.11 + 0.005 + 0.102 + 0.11 + 0.010 = 19.337m
area = circumference x width = 4,594.348m²

Roof hull: assume flat cylinder (not arched), and not including greenhouse or observation deck.
Pi x (2 x inside radius)
area = 4,274.808m²

Total ring hull area: 4,594.348m² + 4,274.808m² + 2 x 603.14m² = 10,075.436m²
Ring hull mass = area x 36.76 kg/m² = 370,373 kg

This doesn't include interior pressure bulkheads or pressure doors. Can anyone help with that before we start with cabin mass?

RobertDyck · 2020-09-20 02:24:07

A couple more small cabin changes.
I said a "single" cabin has a queen-size Murphy bed. The floor plan from Norwegian Epic cruise ship shows toilet and shower stall on opposite sides of the door. If the shower is on the same side, so little room between shower stall and foot of the bed, then washroom/restroom is a standard location for economy class cabins. And the cabin for Norwegian Epic has the sink outside the washroom/restroom, but I would put it with the toilet. To economize space, the sink built into the top of the toilet tank. Interior cabins could have transparent shower stall, but made of polycarbonate (Lexan) instead of glass to save weight. And when configured as an economy cabin, an opaque covering as thin as a piece of cardboard would cover the outside of the shower. This means one design for "standard" cabins that can be configured as single or economy simply by changing furniture.

Furthermore, I started by saying 162 economy cabins plus 90 single. Standard cabins organized into pressure compartments in case of hull rupture. Each pressure compartment with common water storage, final water filtration (grey water to potable), and air conditioning (refrigeration). This would add up to 162+90=252 cabins. I would like to add 4 more standard cabins so the total equals 256. So 16 cabins per pressurized compartment, that means 16 compartments. That is 4 outside cabins on the aft side, 4 inside cabins on the aft corridor, 4 outside cabins on the forward side, 4 inside cabins on the forward corridor.

Do we want to subdivide pressure compartments in half? So the wall between aft inside cabins and forward inside cabins is a pressure wall? Both sides of the compartment would still share services, but a hull rupture in a cabin along the after corridor would not affect cabins along the forward corridor. Or vice versa.

tahanson43206 · 2020-09-20 05:54:09

For RobertDyck re #329 and #330

Impressive work ... It is good to see the Circle Y design developing! There's a lot to do to create a ship on this scale, and this is a step forward.

We do need more folks working on this. There are (by now) thousands of aerospace engineers who have transitioned away from day-to-day duties, buy who have not yet lost the abilities they developed over long careers. A way to reach them with an invitation to assist would be helpful.

(th)

SpaceNut · 2020-09-20 07:06:08

Post 329 is essentially a Cygnus payload module can without the solar panel engine module .

RobertDyck · 2020-09-20 15:00:34

Alright. Cygnus Spacecraft
Cygnus standard PCM dry mass 1,500kg, enhanced 1,800kg
Diameter 3.07m
PCM length: standard 3.66m, enhanced 5.05m
passive CBM: 200kg
CBM length: 0.4m

cylinder:
length without CBM: 5.05 - 0.4 = 4.65m
difference between standard (2 segment) and enhanced (3 segment): 5.05-3.66=1.39m
so cylinder length of enhanced: 1.39 x 3 = 4.17m
end cone length: (4.65 - 4.17)/2 = 0.24m
area: Pi x 3.07m x 4.17m = 40.2m²

end truncated cone:
5.192982441052105m² each

back end disk:
Pi x (1.8/2)² = 2.54469m²

Note: Wikipedia article on CBM says diameter 1.8m, but Spaceflight101 article on Cygnus mentions the hatch "in the 127-centimeter [CBM] ring". I'm assuming 1.8m is outside diameter, 1.27m is inside diameter.

PCM surface area: 40.2m² + 2 x 5.192982441052105m² + 2.54469m² = 53.13m² (rounded)
enhanced dry mass without CBM: 1,800kg - 200kg = 1,600kg
density = 1,600kg / 53.13m² = 30.1148 kg/m²

That's a little lighter than Leonardo's 36.76 kg/m². And I used figures for Leonardo from its MPLM configuration, not PMM.

RobertDyck · 2020-09-20 15:16:51

Note: rotation rate of 3 rpm = Mars surface gravity
1.981 rpm = Moon gravity
4.87042 rpm = Earth gravity

RobertDyck · 2020-09-20 22:12:07

Next there's the spokes, hub, cargo hold, propellant tank, main engine, course correction engines.
Cabins, life support, radiators, photovoltaic panels.
Manoeuvring thrusters including spin up/down. Propellant tanks for manoeuvring thrusters.
Propellant transfer plumbing. Manoeuvring thrusters will be on the outside surface of the ring, tanks located close to thrusters like thruster quads for Apollo SM, however propellant has to get there. Propellant for main engine can be delivered via connection near the engine itself (aft end), but any tanker must dock on an axis of rotation. That means manoeuvring thruster propellant must be delivered via plumbing from the hub, down spokes, to tanks near the thrusters. May as well deliver manoeuvring thruster propellant via primary docking hatch. Russian docking hatch has an optional propellant connection.
Air. Mass of breathing air in a vehicle this large must be factored in.

tahanson43206 · 2020-09-21 06:51:42

For RobertDyck re topic as it develops ...

You may have mentioned water, but for the sake of completeness that could be added to Post #335.

I'd like to point out that Post #334 lacks a wrapping that would make it meaningful to a new reader who comes upon the topic.

The context (as I understand it) is that you are describing simulated gravity in a vehicle with a 56 meter radius.

***

You are going to need volunteer assistance as you expand the range of design focus. At some point, you are going to have enough thought sequences in play that the project will bog down if you do not have trusted associates to take on detailed development.

For SpaceNut ... we have discussed recruiting before, but nothing has come of the conversation. I'd like to point out that RobertDyck's inititive is continuing to move from fantastic vision to real-world plan. At some point, continued development of that topic will greatly benefit if qualified persons agreeable to RobertDyck can be enlisted to help.

There are many specialties that could be considered, but (perhaps) structural engineering skills would be most useful at this point, to help to identify flows of force in a vehicle of this size, and to prescribe materials and characteristics suitable to meet whatever the challenges may be.

(th)

tahanson43206 · 2020-09-21 10:54:11

For RobertDyck re topic ...

Here is a link to a web site written at a consumer level, for (I presume) prospective cruise ship passengers.

https://www.cruisemapper.com/wiki/757-c … ion-design

The pages discuss construction of modern cruise ships in modular form.

As of 2020/09/21, it is my understanding you have chosen to plan for construction on orbit using teleoperation equipment. I think this is an interesting idea for several reasons, not least of which is the beneficial effect the development of a robust on-orbit teleoperation construction industry would have on employment for Earth citizens, who would be able to work from home using Equipment Pods provided by their employer, or purchased the way some long haul truck drivers buy their own tractors, in order to be independent and able to work on any available project.

At the same time, I gather that you are not unwilling to consider procuring some equipment already constructed on Earth, so (from my point of view) your project seems to incorporate a nice variety of employment opportunities.

A partnership with a cruise ship manufacturer would seem (to me at least) not out of order.

The most likely outcome of your efforts seems (again, to me at least) to be a ship with your name proudly borne on whatever the equivalent of the prow and stern might be.

(th)

RobertDyck · 2020-09-21 12:00:37

tahanson43206 wrote:

The context (as I understand it) is that you are describing simulated gravity in a vehicle with a 56 meter radius.

No. I said radius to surface of the floor would be 37.6992 meters. Plus flooring and thickness of the hull.

tahanson43206 wrote:

A partnership with a cruise ship manufacturer would seem (to me at least) not out of order.

Actually, in post #225 I posted a link to a manufacturer of composite cabins for cruise ships. I was actually thinking of asking them to manufacture custom cabins for our ship.

tahanson43206 · 2020-09-21 15:11:10

For RobertDyck re #338

Thanks for your clarification ... I recognize a writer may post thoughts in the heat of creative frenzy, without context.

However, there is plenty of time after the fact to go back and tidy up. It would be helpful to a person (not currently a member of the forum) who is trying to follow your topic, if you would add just enough additional information so they can put whatever the post is about into context.

***
Please contact the company! I'd recommend a bit more flexibility in your thinking. They could become valuable partners, with a full suite of suppliers to bring into the project if and when appropriate.

I'm also hoping you will contact the Canadian Arm manufacturers/suppliers ... they would seem (to me at least) logical partners to build the teleoperation equipment you've indicated you'd like to use to assemble the components you send aloft.

(th)

SpaceNut · 2020-09-21 16:26:47

Reply for post 336

For SpaceNut ... we have discussed recruiting before, but nothing has come of the conversation. I'd like to point out that RobertDyck's inititive is continuing to move from fantastic vision to real-world plan. At some point, continued development of that topic will greatly benefit if qualified persons agreeable to RobertDyck can be enlisted to help.
There are many specialties that could be considered, but (perhaps) structural engineering skills would be most useful at this point, to help to identify flows of force in a vehicle of this size, and to prescribe materials and characteristics suitable to meet whatever the challenges may be.

The real problem is bucks to pay for the build of engineering staff to bring the building into process. With out a Mars Society funding cash flow we are left to only thoughts here that we believe can work.

The plan would be is to turn business opportunities into that cash flow in order to be able fund these much larger projects to build for getting to mars.

This part of the space x model....

RobertDyck · 2020-09-21 16:27:29

Yea...the Canadian Arm manufacturer... Well... The original CanadArm for Shuttle was built by Spar Aerospace. The robotics division of Spar Aerospace was sold to MacDonald, Dettwiler and Associates as MD Robotics, a subsidiary of MDA. CanadaArm 2 and it's accessories were built by MDA. In 2008, MDA attempted to sell it's space division to ATK in the US. MDA wanted to focus on developing software for real estate industry, and get out of space entirely. But there were issues.

RadarSat was owned by the Canadian Space Agency, but the Canadian government made a deal with MDA so RadarSat 2 was actually owned by MDA, time was leased to the CSA. So selling MD Robotics to an American company meant that American company would own RadarSat 2. When RadarSat was built, the US military didn't have anything capable of doing what it did. The deal with NASA to launch the first RadarSat was NASA gets 30% of observation time of the satellite instead of pay cash for the launch. The US military got to use it as well. I believe after that the US military built a radar satellite of their own, but then Canada built RadarSat 2. It was more capable than anything else. Both Canadian radar sats were intended to measure sea ice in the Canadian arctic, but the US military pointed out the first one could detect the wake of ships at sea; it couldn't detect ships directly, but based on the wake it could detect every ship at sea on the planet! RadarSat 2 had higher resolution; it could detect the steel hull of ships directly, so even if a ship stopped so no wake, RadarSat 2 could still see it. One use was to monitor ships travelling through Canada's Northwest passage. So selling this satellite meant Canada would no longer control this key technology for national defence. The Canadian government did not allow the sale.

Cute story: when Canada wanted to build the first RadarSat, they had CSA partner with NASA. When NASA saw the specs of what they wanted to do, NASA said it was impossible. So CSA did it on their own. When finished, CSA went to NASA and asked them to launch it. In return NASA would get 30% observation time. NASA's first response was "What! You built it? But that's impossible!" NASA took the specs to the US military who said they don't have anything that can do that. The US military did not want Canada to have that so did not give permission. NASA had to tell CSA. Managers at CSA did not get upset, they just said they would ask Russia to launch it for them, so Russia would get the 30% observation time instead. 24 hours later NASA called back to ask "When do you want it launched?" (True story)

My concern is although the space robotics division is still owned by MDA, they're really not interested in space.

tahanson43206 · 2020-09-21 17:40:07

For RobertDyck re #341

Thanks for the back story on the Canadian achievements! I had read the story about spotting ship's wakes (and upwelling from submarines) before, but did not put it together with the Canadian system. I ** think ** the story I am thinking about was accuracy of laser measurements of the ocean surface, so accurate the upwelling from a travelling submarine could be detected. The radar system you've described would be able to punch through some distance in the ocean.

I'm here to try to help at moments like this ... Please consider asking MDA if they want to help with teleoperation to build the first Interplanetary Passenger vessel. There is a chance you might receive a decline, but I'll bet (if you do) it will be a courteous one.

On the other hand, you may catch the management team trying to figure out how to extend the real estate market. I can't hurt to ask.

(th)

Calliban · 2020-09-21 17:43:02

RobertDyck wrote:

Yea...the Canadian Arm manufacturer... Well... The original CanadArm for Shuttle was built by Spar Aerospace. The robotics division of Spar Aerospace was sold to MacDonald, Dettwiler and Associates as MD Robotics, a subsidiary of MDA. CanadaArm 2 and it's accessories were built by MDA. In 2008, MDA attempted to sell it's space division to ATK in the US. MDA wanted to focus on developing software for real estate industry, and get out of space entirely. But there were issues.
RadarSat was owned by the Canadian Space Agency, but the Canadian government made a deal with MDA so RadarSat 2 was actually owned by MDA, time was leased to the CSA. So selling MD Robotics to an American company meant that American company would own RadarSat 2. When RadarSat was built, the US military didn't have anything capable of doing what it did. The deal with NASA to launch the first RadarSat was NASA gets 30% of observation time of the satellite instead of pay cash for the launch. The US military got to use it as well. I believe after that the US military built a radar satellite of their own, but then Canada built RadarSat 2. It was more capable than anything else. Both Canadian radar sats were intended to measure sea ice in the Canadian arctic, but the US military pointed out the first one could detect the wake of ships at sea; it couldn't detect ships directly, but based on the wake it could detect every ship at sea on the planet! RadarSat 2 had higher resolution; it could detect the steel hull of ships directly, so even if a ship stopped so no wake, RadarSat 2 could still see it. One use was to monitor ships travelling through Canada's Northwest passage. So selling this satellite meant Canada would no longer control this key technology for national defence. The Canadian government did not allow the sale.
Cute story: when Canada wanted to build the first RadarSat, they had CSA partner with NASA. When NASA saw the specs of what they wanted to do, NASA said it was impossible. So CSA did it on their own. When finished, CSA went to NASA and asked them to launch it. In return NASA would get 30% observation time. NASA's first response was "What! You built it? But that's impossible!" NASA took the specs to the US military who said they don't have anything that can do that. The US military did not want Canada to have that so did not give permission. NASA had to tell CSA. Managers at CSA did not get upset, they just said they would ask Russia to launch it for them, so Russia would get the 30% observation time instead. 24 hours later NASA called back to ask "When do you want it launched?" (True story)
My concern is although the space robotics division is still owned by MDA, they're really not interested in space.

I like it. Too bad the UK didn't pull a similar trick when the yanks refused to let concord fly to New York, because they were jealous that we had built something they couldn't.

kbd512 · 2020-09-21 18:46:25

Robert,

I still fail to understand this idea that Canada ever required permission from the US to launch their own RadarSat into space using their own launch vehicles. No such permission is required and it never has been. I'm quite happy that Canada was willing to share its radar satellite technology with the US, in much the same way that NASA and USAF shared their space launch vehicles.

Calliban,

Concorde did fly to New York / Los Angeles / San Francisco. The only reason it was initially prohibited is that supersonic flights over land are, as of this month in 2020, still against FAA regulations. The only aircraft that may break Mach are military jets, and only when those jets are flying contingency missions (interception of incoming enemy aircraft or missiles or outgoing B-1B bombers or participating in training flights in designated training areas far away from population centers). If you were in the military and broke the sound barrier over the US for any other purpose, then you'd be flying a desk very shortly thereafter. There's been a long-standing prohibition on supersonic flights across the US due to the lawsuits that followed the destruction of private property destruction from the sonic booms generated. We haven't built any supersonic airliners because there's functionally no market for the service provided, except amongst the ultra-wealthy flying between continents.

A grand total of 20 Concorde airframes were built. To my knowledge, they were operated at a profit only because the British and French governments paid for the development costs. Concorde was a most impressive feat of engineering, but like so many other impractical ventures, never destined to be anything more than pyrrhic symbols of national prestige. By way of comparison, 1,558 Boeing 747s and 242 Airbus A380s were built. Boeing gave up on SST when they realized it wasn't practical and never would be. Skylon may succeed where Concorde failed, but that remains to be seen.

It's very odd to me that both of you think Americans are jealous of your feats of engineering, rather than proud that one of our allies possessed the technical prowess and determination necessary to create something like a RadarSat or CanadArm or Concorde. Until the past several decades or so, the American military and commercial sector were objectively better judges of what was practical vs impractical. That said, America has British / French / German cannons, a joint American-German tank design (elements of which ultimately evolved into the Abrams and Leopards, only differing materially in the power pack selected), British armored fighting vehicles, Australian frigates, British training aircraft and jet engines, Japanese / Korean / Singaporean electronics, virtually all of our small arms are now Belgian or German made- even if some are American designs, and most of our partner nations have been deeply involved in the creation and manufacture of the world's most sophisticated and capable 5th generation stealth tactical fighter. All of our airlines have healthy stocks of Airbus aircraft as well. Therefore, the notion that we think something is "better" solely because we made it is... not connected in any way to reality.

RobertDyck · 2020-09-21 19:49:18

kbd512,

Canada does not have satellite launch capability. In the late 1950s, the company A.V. Roe Canada (aka Avro) built the Arrow for the Canadian air force. One proposed application was to launch small satellites on a rocket launched from the belly of an Avro Arrow. However, the aircraft was cancelled. By the way, the US Pegasus rocket was a US company copying this Canadian idea. Canada built sounding rockets (Black Brant), but has never built a launch vehicle capable of achieving orbit.

Calliban · 2020-09-21 20:03:54

Yeah, Kbd, I wondered if it was something like that. Just thought I would pull your chain :-)

RobertDyck · 2020-09-21 20:59:30

kbd512,

Canada didn't get over cancellation of the Avro Arrow for generations. I believe Millennials and Generation Z are ignorant.

The Soviet Union test flew the first Tu-95 bomber, known by the NATO designation Bear, in 1952. The Canadian air force came up with requirements for an all weather interceptor to shoot it down. The Bear bomber was better in every way than the American B-36; America's response was to develop the B-52. Canadian interceptor requirements were finished and given to engineers in 1953. When Canadian engineers first saw the requirements, they cried that it's impossible! It can't be done! They cried, got drunk, then in the morning when they sobered up, they got to work. First flight of Avro Arrow mark 1 was 1958. It was better in every way than any other fighter of its time: super cruise @ mach 1.5 at 50,000 feet, max speed mach 2.5 in flat level flight (with after burner), or mach 2.7 in a dive, all radar systems onboard (American radar used ground computers to recognize signals), and fly-by-wire. They even planned an upgrade to the American AIM-7 Sparrow missile to make it fire-and-forget. At the time it required the fighter pilot to remotely "fly" the missile into its target. Canadians were proud. But Americans didn't like it. US president John F. Kennedy demanded that Canada cease development. They had the U-2 spy plane, which no fighter in the world could shoot down. But the Avro Arrow could. One excuse was the Soviets would steal plans for the Arrow so they could shoot down the U-2. Canada was planning to sell Arrow fighter jets to all NATO allies, including the US. But the US didn't like it, demanded that all NATO allies *NOT* buy the Arrow. France did place an order for Orenda Iroquois engines, to upgrade their Mirage fighters, but all NATO allies complied with America's demand that they refuse to buy Arrow. Without any orders, Canada couldn't afford the aircraft. There was strong debate in Canada whether to continue or not, but without orders it became so expensive that one of the two major political parties claimed it was a "White Elephant". When that party got elected, development of Arrow limped along for a little while, but eventually it was cancelled.

Ps. It wasn't long before the Soviet Union developed both a missile and a fighter jet capable of shooting down U-2. All on their own, without stealing anything from Canada.

Canadian Baby Boomers and Generation X never forgave America for that.

kbd512 · 2020-09-22 02:23:15

Robert and Calliban,

One of the things that was really perplexing to me about our allies, given their budgetary limitations during the Cold War, was their propensity to bet the proverbial farm on projects that were of questionable military utility. To be sure, the US also engaged in such projects, though it could better absorb the tremendous costs at that point in time. However, this persistent idea of a "leap ahead" super weapon simply will not die.

Robert, your much-loved Arrow was dependent upon a missile system that didn't yet exist. When AIM-7 was deployed in actual combat in Vietnam, it scored 73 air-to-air kills, with just 4 head-on shots from beyond visual range. The rest were fired within visual range. The missiles missed the target, even an unaware pilot, almost 88% of the time. The notion that the AIM-7 was going to shoot down a U2 in the early 1960s is improbable at best. Despite extensive use of the U-2 over enemy territory, which continues to this day, more U-2 pilots have been lost from training accidents than to enemy action. The Soviets managed to shoot down U-2s by being willing to expended any number of missiles to attempt to bring them down. As with horse shoes, close counts when the missiles in question have warheads the size of a small piece of air-to-ground ordnance. The F-106 was a more affordable fighter than the Arrow, but both jets were basically DOA concepts. Simple physics dictated that the Nike missile, with Mach 3 to Mach 4 flight speeds, was a vastly more economical way to down turboprop-powered bombers or high altitude supersonic bombers traveling in straight lines. Simple physics and economics can be a real buzzkill when it comes to practical weaponry. Nike Hercules had a warhead of about the same weight as a 1,000 pound iron bomb. If American military planners thought that the existing high performance century series of fighters were impractical and quit producing them after spending billions on marginal capabilities improvement or development failures, try to imagine what they thought of a largely untested airframe claiming capabilities that they determined were not well suited to dealing with the emerging threats. Even if Arrow was put into full production and shot down all incoming enemy bombers, none of that mattered in the face of ICBMs. That's why the F-106 was the last single-purpose interceptor airframe produced.

Amateurs like to look at fighters as super weapons and compare how fast they are or how much they can carry, whereas practical military planners look upon them as tools to effectively accomplish critical missions. This was abundantly clear to me as a child, admittedly because I was intensely interested in the subject of what makes a weapon practical, rather than marginally better than the next one similar to it. I came to the conclusion that much of the capabilities that the US and other western militaries purchase is grossly impractical, no matter who we're fighting.

A good fighter possesses the following characteristics:

1. An airframe design appropriate to the designated role or capability - This is the first major stumbling block where both experts and amateurs alike fall down. For all practical purposes, fighter jets spend nearly all of their operational lives at high subsonic speeds going to or from targets in roughly straight lines, very rarely using supersonic dash speed due to the impractical fuel burn rate and the loss of capability when you arrive in the threat area, only to be perilously close to bingo fuel. In most scenarios, maximum performance turns following ordnance release are far more common to execute.

2. Sensors and weapons appropriate for the mission capability - Apart from an inappropriate airframe design, nothing else will detract more from accomplishing a mission than marginally capable sensors and weapon systems or poor cockpit layout / design. It's very tempting to load up a fighter with so many missiles and bombs that they become use / lose hardware that must be expended merely to return and land. A large ordnance load is only impressive from the standpoint of the ability to substitute fighter-bombers for purpose-built bombers, which have traditionally delivered the lion's share of the ordnance, despite relatively small numbers. For all practical purposes, the F-4s or F-8s of the Viet Nam era would've been far better armed with 8 Sidewinders and an internal gun. The Sparrows were not a major factor in aerial kills. The primary purpose of the radar should've been searching for targets to close with and destroy using IR-guided weapons that, even in those days, were known to be pretty lethal. The Pk of existing radar guided weapons, even when fired from relatively modest ranges against maneuvering targets, was abysmal. For strike missions and close air support, 8 of the 500 pound bombs should've been specified as the practical limit. The number of ground targets that could only be killed with heavier bombs was slim to nonexistent.

3. A generous internal fuel capacity for long range - A fighter is useless if it's constantly sucking its fuel tanks dry, requiring frequent tanking events to remain airborne. I would rather have an excellent 7g fighter with double the range of a truly stunning but short range 9g fighter. All 4th generation jets or earlier were festooned with large capacity drop tanks because insufficient internal fuel was carried. The requirement to carry so much external fuel drastically reduced their maneuverability limits and increased drag to the point that all of them, no matter who made them, were functionally subsonic aircraft with a practical combat radius. After the 3rd generation of jet fighters was still carrying enormous external fuel tanks on the wings and fuselage, it should've been painfully obvious that pure speed was of greatly limited utility when combat loaded aircraft were never capable of reaching their maximum speeds or maneuverability limits.

4. A design that permits easy access to systems for maintenance and maintenance procedures that can be accomplished with 2 to 4 maintainers using hand tools. While there were truly excellent designs put into service, from a maintenance standpoint, there were also absolute nightmares that never should've been permitted to enter service, as-designed.

5. Adaptability to a range of missions - However truly excellent an interceptor may be at racing towards subsonic bombers at high supersonic speeds, this single design criteria drastically reduces the practicality of the design for other purposes, because pure speed dictates so many design features as to make the airframe functionally useless for other missions. In practice, the theoretical speeds achievable by a nearly clean airframe were never used in combat on account of the aforementioned fuel consumption issue.

The progress associated with fighter jet technology during the early Cold War era was so rapid that there was little point in purchasing and fielding thousands of different types of jets with marginal improvements to ranges or payloads with ever-increasing maximum speed figures that were known to be useless in practical combat. If anyone had demanded practical demonstrations of how the capabilities that were actually used in combat would be applied to new fighter jet designs, this would've been readily apparent. I do understand the military need for the F-100, the F-8 and its A-7 derivative, and the F-4. Those designs provided a logical mix or progression of military capabilities that saw extensive and successful use in actual combat. The A-4 was praised for its good qualities, yet all of the services and foreign operators spent an inordinate amount of time trying to make them more capable than the technology of the time would allow for. At the same time, there were at least a trillion dollars squandered on marginal performance improvements from the plethora of early 1950s / 1960s fighters and the teen series fighters, which never materialized in combat on account of how heavily loaded (overloaded) those jets were / are.

We could've skipped the F-14 / F-15 / F-16 / FA-18 and apart from having vastly more defense dollars to materially improve the avionics, sensors, and weapon systems capabilities of an extant F-4 fleet, virtually no real combat capabilities would've been given up to the Russian MiG-29s and Su-27s. The F-4 with turbofan engines and 1,000 gallon conformal fuel tanks provided such a dramatic range and speed improvement that combat radius was easily improved by 50%, while simultaneously reducing aerodynamic drag by 40% over a conventional 600 gallon centerline fuel tank. According to the people who worked on F-15 procurement, the numerous F-4 improvements threatened the development of the then-new F-15 to the point that development was halted. Through structural strengthening and hydraulic system enhancements, maneuverability was improved to the point that a combat loaded F-4 would've been very comparable to a combat loaded F-14. It would've given up some sustained turning performance to the F-14 / F-15 / F-16 / F-18, but that's rarely used to gain a positional advantage. Extended turning engagements with a competent adversary are a fantastic way to get yourself killed. It's also very easy to turn a 9g jet into a 7g or 5.5g jet by adding enough fuel or weapons to remain mission relevant.

Similarly, fitment of modern engines and avionics to the old F-100s would've provided something functionally equivalent to what the original F-16 design was intended to be. The F-20 matched the F-16s spectacular kinematic performance for far less money, and again, presented a reasonably affordable and highly capable option for allied nations to purchase, if they so desired.

Anyway, had America and her allies spent our money procuring better avionics / sensors /weapon systems, we'd still have gross overmatch capability against Russia or China if they decided to start invading their neighbors. In closing, Arrow was much like the F-111, a technical miracle but impractical and a maintenance and procurement nightmare. 13 F-111 crews were lost flying into terrain and 1 to enemy action. If it's more dangerous to simply fly a jet than anything the enemy can do to you, then maybe you have an impractical machine or unreasonable set of mission requirements.

RobertDyck · 2020-09-22 04:59:37

kbd512 wrote:

One of the things that was really perplexing to me about our allies... was their propensity to bet the proverbial farm on projects that were of questionable military utility.
...
Robert, your much-loved Arrow was dependent upon a missile system that didn't yet exist.

The Sparrow missile did exist. Pardon me if the code name "AIM-7" is not right. In the 1950s the manufacturer of the Sparrow missile tried to develop a fire-and-forget guidance system, but couldn't get it to work. So what was deployed was a system where the fighter pilot had to use a radio remote control system to "fly" the missile as if it were a toy aircraft. Canada did not intend to develop a new missile, just to finish development of the guidance system. And the Canadian intention was not "beyond visual range"; instead the intent was within visual range.

Before you give me a list of requirements for a good fighter, realize the Avro Arrow as not designed to be an air superiority fighter. It was a purpose built interceptor. The difference is an interceptor is designed to fly very fast, fire an air-to-air missile, then turn around and run away. It doesn't need dog fighting capability, because an interceptor flies so fast it doesn't get into a dog fight.

You can't call Avro Arrow "questionable military utility" because it was designed for a very specific mission. It was designed to shoot down a Tupolev Tu-95 bomber, known by the NATO designation "Bear". When Russians heard that Americans called their new bomber "Bear", they were flattered. That's the animal symbol of Russia, so they decided to accept that name. Avro Arrow was designed to intercept an Bear bomber while flying over Canadian territory, before it reaches the border with the lower 48 states of the US. And before it reaches any Canadian cities. As I said, after the first prototype of the Tu-95 was flown, the Canadian air force came up with specifications for a new all weather interceptor to shoot it down. The specifications required it to supercruise at mach 1.5, and maximum speed with after burner of mach 2.0 in flat level flight @ 50,000 feet. But as built the aircraft could fly mach 2.5 at that altitude. The Arrow was ambitious, but the aircraft not only achieved every design goal, it exceeded some. It was designed to operate in Canada's north, hundreds of miles or even a thousand miles from any military base. It had to be self-contained and independent. This was some airy-fairy thing, it was practical utility. At a time when US military fighters had a radar system dependant on ground computers so their radar wouldn't work if they flew beyond radio range, the Canadian interceptor had to be self-contained.

Again, as for "questionable military utility", the Soviets went onto to develop the Tupolev Tu-160 bomber, known by a Russian name that translates as "White Swan" but American military calls it the Blackjack. This bomber can fly at mach 2.0! An FA-18 Falcon or the Canadian version the CF-18 cannot catch it. An F-35 flies even slower. Russia has developed low frequency radar that is very capable of detecting an F-35. The only American fighter capable of even catching a Tu-160 is the F-22 Raptor; just barely. Congress passed a law that the F-22 cannot be exported to any country, not even Canada. The US and Canada have unified air defence under NORAD, but Congress doesn't care. An Avro Arrow could intercept a Tu-160 easily. If Canada had Avro Arrow, it would still be relevant today.

Ps. Avro Arrow was able to race to it's target at high speed with high fuel efficiency and a large fuel load. I don't think you even know how large Canada is, or how vast distances are from air bases. Avro Arrow was able to supercruise because that means flying a supersonic speed without after burner. An after burner sucks fuel like crazy. An Avro Arrow had to fly from Cold Lake Alberta to a target flying over Canadian arctic islands, shoot down its target, then fly back to base. It can't do that if its using after burner the whole way. That's why it had to supercruise. Tu-95 Bear could cruise at mach 0.85 so Arrow was designed to cruise at mach 1.5.

kbd512 wrote:

Anyway, had America and her allies spent our money procuring better avionics / sensors /weapon systems, we'd still have gross overmatch capability against Russia or China if they decided to start invading their neighbors.

Again you missed the point. Canada developed fly-by-wire avionics in the 1950s. Requirements for Arrow were written by the Canadian air force in 1953; engineers quickly realized it would require fly-by-wire. The first American fighter jet to use fly-by-wire was F-16 Fighting Falcon, which first flew in 1974. Arrow first flew in 1958. Yea, sure, the fly-by-wire for F-16 was better, but that doesn't change the fact Arrow did it 2 decades earlier. America wasn't able to develop a fire-and-forget guidance system for Sparrow missiles, so Canada inteded to finish the job. It would have been sold to our American allies. The problem isn't working together, America's allies are willing to do that. The problem is American military manufacturers don't like it when a non-American builds something much better than anything they can make. And Congress is in the back pocket of lobbyists from American military contractors.

tahanson43206 · 2020-09-22 06:02:07

For RobertDyck and kbd512 ....

This has been a fascinating discussion but I believe it belongs in Chat.

Please keep a tight focus on RobertDyck's Large scale colonization ship.

There have been a LOT of proposals for simulated gravity for long term space flight. I think RobertDyck's concept has potential to collect supporters, if he will keep moving it along, and if everyone in the forum will try to help in whatever way they can.

***
For RobertDyck ... The original specification of 76 meters diameter for the rim of the habitat ring remains in place in Fusion 360 ... I had allowed the 56 meters for 1 g at 4 RPM figure to settle into my mind so that it overwhelmed the 76 meter specification. I will go back to correct any text I may have entered in error relating to the images posted in the forum. I think there is only one but will check to be sure.

Edit#1: Correction completed.

(th)

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