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Apollo on tranquilizers

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gruff5
951729.  Mon Nov 19, 2012 1:21 am Reply with quote

We've been told (and then disappointed) that "Apollo on steroids" would be returning to the Moon.

How about smaller, cheaper, faster instead?

I'm currently in the Philippines and they are the smallest nationals I've ever seen.

If we today sent a moon rocket with two below-average sized Filipinas aboard, couldn't said rocket be half the size (or less) of Apollo?

 
Posital
951968.  Tue Nov 20, 2012 12:46 pm Reply with quote

Kinda, but most of the weight of the rocket is the fuel to propel the rocket in the first place...

 
gruff5
952418.  Fri Nov 23, 2012 4:06 am Reply with quote

Posital wrote:
Kinda, but most of the weight of the rocket is the fuel to propel the rocket in the first place...


Well, duh, I think I knew that!!!

But if the payload is reduced by 50% (or perhaps more?) - as I'm suggesting, then the mass of the overall rocket&fuel-combination will also be reduced by 50% (or more?). If my logic is faulty, please explain why?

A Soviet rocket of that size existed in the 1960s and maybe the Chinese will have such a rocket soon. I think the peoples who inhabit southern China are of similar stature to the Filipinos.

Now, dear QIers - discuss!!

 
dr.bob
952426.  Fri Nov 23, 2012 5:51 am Reply with quote

The payload won't be reduced by 50%.

If you want to land on the moon, you'll need a Lunar Module. The one for the Apollo mission had a mass of 14,696 kg.

If you want to come back to Earth again, you'll need a Command Module. The one for the Apollo mission had a mass of 30,332 kg.

That's the payload you'll need to get up there. Reducing the weight of the astronauts by 50% will reduce the weight of the total payload by a little less than 0.2%.

 
PDR
952457.  Fri Nov 23, 2012 7:46 am Reply with quote

And don't forget that unlike the original missions of the 60s, many of today's astronauts are women. So you have to factor in the extra weight of handbags, cosmetics, back-issues of Hello and the soft furnishings/ornaments they'll demand for the crew spaces.

PDR

 
dr.bob
952472.  Fri Nov 23, 2012 10:17 am Reply with quote

Really, pretending to be a tedious, sexist arsehole might be funny on particular threads, but bringing it into every thread is even more tedious than if you really were just a tedious, sexist arsehole.

 
PDR
952488.  Fri Nov 23, 2012 11:56 am Reply with quote

I'm just providing you with the opportunity for at least one decent "Hurumph!" per day, Doc. All part of the service (and at no extra charge, too)

PDR

 
gruff5
954436.  Wed Dec 05, 2012 9:52 pm Reply with quote

dr.bob wrote:
The payload won't be reduced by 50%.

If you want to land on the moon, you'll need a Lunar Module. The one for the Apollo mission had a mass of 14,696 kg. ....


Dr Bob, I expected better of you (a scientist?) than this somewhat lazy response!

I was not suggesting a Saturn V and Apollo craft would be dusted off, mothballs taken out, bought by China and sent on its way. I was suggesting that a country like China, who has her eyes firmly set on manned spaceflight, could get to the moon with a much smaller rocket than the Saturn V.

I hardly think they will be asking it the JSC and Smithsonian museums could kindly send them their old Apollo rust buckets. The Chinese will be designing their own spacecraft, de novo.

As I've already suggested, their new designs of command modules and lunar landers can be based around small stature men (or possibly women) from the south of China.

Michael Collins and the other command module pilots were pretty redundant, even in 1969. With todays superior electronics technologies, a crew of only 2 will suffice. Note that even the 40 year old design of the Progress re-supply ship can make automated dockings with the ISS.

In addition, I expect the American Apollo craft were designed with all kinds of fail-safes and mechanical redundancies that the Chinese won't feel necessary for a reasonable chance of their nationals returning alive.

 
dr.bob
954453.  Thu Dec 06, 2012 5:35 am Reply with quote

gruff5 wrote:
As I've already suggested, their new designs of command modules and lunar landers can be based around small stature men (or possibly women) from the south of China.


The stature of the astronauts really has very little bearing on the overall mass of the spacecraft.

Consider just the LEM for a moment. The vast majority of the mass of the Apollo LEM was made up of components such as radio communications, various sensors around the craft, oxygen tanks, engines for landing, etc. The mass of the astronauts, even today with smaller and lighter electronics, would be such a small percentage of the overall mass of the system that sending slightly smaller people would make no appreciable difference to the size of the payload.

Even a very simple, non-spacegoing craft like the Red Bull Stratos capsule, designed with all the latest technology, weighed in at a hefty 1,315kg. I'm not exactly the lightest person in the world, but even I would only make up about 7% of the total mass of that system, and that's just a glorified balloon gondola.

gruff5 wrote:
In addition, I expect the American Apollo craft were designed with all kinds of fail-safes and mechanical redundancies that the Chinese won't feel necessary for a reasonable chance of their nationals returning alive.


If the Chinese launched a space craft tomorrow, it would be tracked by the world's media every step of the way. If it failed to come back, everyone would know about it and it would be a massive PR disaster.

Of course any Chinese space craft would have the same kind of fail-safes and redundancies (if not more so) thus adding to the mass of the craft.

 
Efros
954463.  Thu Dec 06, 2012 6:31 am Reply with quote

We obviously need some Cavorite.

 
PDR
954487.  Thu Dec 06, 2012 8:10 am Reply with quote

If the crew-size to be accomodated was smaller then the primary saving would be a small reduction in the volume of the crew spaces of the cabin. These spaces are made of air, which doesn't weight very much. There would be a small corresponding reduction in the size of the inclosing structure, but the difference is very small and amounts to a couple of kilos of 22-30swg light alloy (these craft are made from paper-thin materials partly because that's all that's needed and partly because of concerns over what happens to high-energy cosmic radiation and particles when they pass through thicker metals.

You could factor this weight saving by two or three for the corresponding reductions in fuel and fuel-container mass, but we're still talking about tiny differences.

The idea that the chinese have reduced "elfen safety gone mad" requirements don't stand scrutiny. The near-neighbour comparison would be to look at chinese fast-jet combat aircraft which, as far as we can determine, are engineered to very similar standards to those of the sophisticated western nations. We are observing their progress in developing a naval aviation capability with a new aircraft carrier and newly-developed maritime aircraft - they appear to be following exactly the same design-qualification/verification process as is used by the UK, USA and France rather than an abreviated "JFDI process.

The US Spacecraft don't have extensive failsafe systems - they have instrumentation and telemetry to allow the status-monitoring systems to be ground-based (to save weight) and to reduce the number of crew required (by passing crew functions to mission control). The determination that three on-board crew are required came from analyses of failure modes and emergency scenarios, together with task analysis of the range of disaster-recovery actions that might be needed. There are a significant number that would need two space-walking people (due to size and mass of the objects to be repaired) plus one inside the capsule to maintain the safe environment. Three is also the minimum number required to cover sleep-cylces on a long-endurance mission Automation wouldn't change this, although it would reduce the number of people needed in mission control on the ground.

PDR

 
suze
954539.  Thu Dec 06, 2012 11:51 am Reply with quote

PDR wrote:
The idea that the chinese have reduced "elfen safety gone mad" requirements don't stand scrutiny. The near-neighbour comparison would be to look at chinese fast-jet combat aircraft which, as far as we can determine, are engineered to very similar standards to those of the sophisticated western nations.


Is it true to say that Soviet military hardware didn't pay as much heed to health and safety and Western notions of construction standards as did the stuff that the west was making in the same era?

Or is the notion that Soviet hardware was (figuratively) "made of cardboard and held together with string" worthy of a klaxon?

I know that in the space race era, the Soviets were rather secretive about what they were doing and how they were doing it. They tended not to tell the rest of the world about unsuccessful attempts at space flights, and just buried them in the statistics as "satellite launches". (I can't remember the details, but there was one in the late 70s which crashed back to Earth and scattered radioactive debris across a remote region of Canada. Ottawa sent Moscow a rather large invoice for clearing it up; Moscow didn't pay it.)

 
dr.bob
954622.  Fri Dec 07, 2012 4:44 am Reply with quote

suze wrote:
I know that in the space race era, the Soviets were rather secretive about what they were doing and how they were doing it. They tended not to tell the rest of the world about unsuccessful attempts at space flights, and just buried them in the statistics as "satellite launches".


This kind of behaviour would be pretty much impossible these days, as far as I can see. With the advance of spy satellites, you can't even build a launch facility, let alone launch a rocket, without many foreign governments being aware of exactly what you're doing.

 
PDR
954671.  Fri Dec 07, 2012 9:10 am Reply with quote

suze wrote:
PDR wrote:
The idea that the chinese have reduced "elfen safety gone mad" requirements don't stand scrutiny. The near-neighbour comparison would be to look at chinese fast-jet combat aircraft which, as far as we can determine, are engineered to very similar standards to those of the sophisticated western nations.


Is it true to say that Soviet military hardware didn't pay as much heed to health and safety and Western notions of construction standards as did the stuff that the west was making in the same era?

Or is the notion that Soviet hardware was (figuratively) "made of cardboard and held together with string" worthy of a klaxon?


Oh it's definitely klaxon-worthy when it comes to their military hardware. Whether or not they held human life in similar regard isn't the issue; it's a matter of the shear amount of time & effort it takes to select & train fast-jet pilots. Some aspects of soviet engineering followed alternative (and not necessarily "inferior") approaches in things like minimising the use of semiconductor/microprocessor technology (partly driven by lower soviet state-of-the-art but mainly by concerns over the "battleworthiness" of these technologies over what could have been a tactical nuke battlefield) or using simpler alloys and accepting shorter lives in engines (no single-crystal turbine blades here!). But the engineering and safety standards were very similar - similar structural margins, similar test/verification/qualification process, similar continuing-airworthiness process etc.

Don't forget that they now sell these aircraft abroad into countries which operate western-style military airworthiness systems, so they need to have the underlying data and analyses just to get onto the shortlist for that. Also remember that after the reunification of Germany the Luftwaffe operated some squadrons of former East-German Mig29s, and had little difficulty keeping them legal.

This gives rise to the "Quite Interesting" Mig29 which is currently at the air museum in Krakow (amazing place, but that's another story). The bit that's QI is that this aeroplane waas originally built as part of a batch for the Soviet air force, where it was in service for a few years. It was then passed to the East German air force where it also served for a few years. When Germany reunified it was accepted into the Luftwaffe where it served until the Typhoons started coming into service. Finally, as a "welcome gift" when Poland joined NATO it was one of a number of Mig29s that germany sold to Poland [allegedly] for one euro each. So this aeroplane has served in four nations and on two "sides" - a fairly novel thing for a modern fast jet.

PDR

 
suze
954697.  Fri Dec 07, 2012 11:59 am Reply with quote

dr.bob wrote:
This kind of behaviour would be pretty much impossible these days, as far as I can see. With the advance of spy satellites, you can't even build a launch facility, let alone launch a rocket, without many foreign governments being aware of exactly what you're doing.


The Americans (at least) certainly had spy satellites observing what the Soviets were up to in the 70s, and they undoubtedly had people inside the Kremlin as well.

So they must have known when space rockets exploded on the ground at the Baykonur Kosmodrom, and where those rockets had been planned to go. Then again, I suppose there was no particular reason for the Americans to tell the world what the Soviets were up to. They knew, but that they didn't mean that they had to tell us.

Trivia: The nearest town to Baykonur Kosmodrom in what is now Kazakhstan is called Tiuratam (in Russian, Töretam in Kazakh); the town of Baykonur (Bayqońır in Kazakh) is two hundred miles away. The name was chosen by the Soviets in a - probably futile - attempt to confuse the Americans about where the base was.


PDR wrote:
Oh it's definitely klaxon-worthy when it comes to their military hardware.


Thanks. I suppose I should have realized this actually, since I have seen The Hunt for Red October ...

 

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