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#51 2018-05-06 15:33:56

Oldfart1939
Member
Registered: 2016-11-26
Posts: 1,780

Re: GPS system for Mars?

In response to Clark:

No, I don't think Louis is either a troll or yanking our chains, but note I didn't rule out possibility (a). Any more comments, however would violate our user agreements facilitating use of the site. It strikes me, however, more as uncontrolled enthusiasm.

OK, I should have prefaced my original post as having the GPS constellation  online to facilitate SpaceX's efforts to bring massive numbers of colonists to the Red Planet. The onboard programming of the approaching spaceship's computers can deal with partial second delays in speed-of-light transmission times from either a ground beacon/radar transponder, and also from the GPS constellation. It's unreasonable to ASSUME (check with GW on the underlying meaning I imply!) that a Earthbound controller can effectively fly or course adjust the inbound Mars planetary lander to a preselected point. There is a several minute lag between sending the course correction and receipt by the lander of said data. The intercommunication among the GPS satellites and a single ground-based station can handle such for the onboard computers. More and more accurately the closer to Mars the incoming spacecraft.

If I were the mission project manager or flight director, I would insist on the GPS satellite constellation for optimal results.

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#52 2018-05-06 17:02:10

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,176

Re: GPS system for Mars?

I won't respond to Clark's nonsense except to say I am the ultimate anti-troll and have been a consistent poster here keeping this site focussed on Mars and Mars settlement even when hardly anyone was posting and those who were attempted to take it off into irrelevant territory.

I'm not too happy to be described as delusional (that's pretty insulting as well) either, given (a) I have pointed to scientific papers and actual developments on laser guidance, enhanced satellite imaging, and AI map reading rather than simply making assertions and (b) there is absolutely no sign that Space X have any intention of putting in place a GPS system prior to landing the BFSs.

Oldfart1939 wrote:

In response to Clark:

No, I don't think Louis is either a troll or yanking our chains, but note I didn't rule out possibility (a). Any more comments, however would violate our user agreements facilitating use of the site. It strikes me, however, more as uncontrolled enthusiasm.

OK, I should have prefaced my original post as having the GPS constellation  online to facilitate SpaceX's efforts to bring massive numbers of colonists to the Red Planet. The onboard programming of the approaching spaceship's computers can deal with partial second delays in speed-of-light transmission times from either a ground beacon/radar transponder, and also from the GPS constellation. It's unreasonable to ASSUME (check with GW on the underlying meaning I imply!) that a Earthbound controller can effectively fly or course adjust the inbound Mars planetary lander to a preselected point. There is a several minute lag between sending the course correction and receipt by the lander of said data. The intercommunication among the GPS satellites and a single ground-based station can handle such for the onboard computers. More and more accurately the closer to Mars the incoming spacecraft.

If I were the mission project manager or flight director, I would insist on the GPS satellite constellation for optimal results.

Last edited by louis (2018-05-06 17:02:54)


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#53 2018-05-06 17:15:24

Oldfart1939
Member
Registered: 2016-11-26
Posts: 1,780

Re: GPS system for Mars?

Louis-

I suspect that SpaceX has been too focused on building the BFR, and not so much the support system to make it functionally operational. But we can see problems as outsiders. That's probably due to us all sitting here with a bird's eye view of things, and being free to flap our lips (actually our brains through our fingertips, typing).
I am certain that once reality hits, and especially as a Mars flight approaches, they will appreciate the presence of accurate and reliable navigational aids; probably the same way a Private Pilot appreciates nav aids when flying an instrument approach in IFR conditions.

Last edited by Oldfart1939 (2018-05-06 17:16:40)

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#54 2018-05-06 18:24:29

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,176

Re: GPS system for Mars?

Well the good thing about such predictions is that eventually they can be tested against reality.  I have backed Space X from the early days, I have backed retropulsive landing and I have backed solar power as the energy source on Mars.  So far it's three out of three.

I predict they will land without a GPS system and that they won't land on sizeable boulders because of the onboard guidance systems/communication with previous cargo landers. I simply don't think Musk will be detoured into spending billions on producing an unnecessary GPS system around Mars for Mission One (although it will be a priority for the following decades, clearly).

I also predict that the Mars Mission will prove to be one of the most profitable enterprises ever undertaken by human beings. In that I currently appear to be standing pretty much alone, even among people who support Musk's plans!

Oldfart1939 wrote:

Louis-

I suspect that SpaceX has been too focused on building the BFR, and not so much the support system to make it functionally operational. But we can see problems as outsiders. That's probably due to us all sitting here with a bird's eye view of things, and being free to flap our lips (actually our brains through our fingertips, typing).
I am certain that once reality hits, and especially as a Mars flight approaches, they will appreciate the presence of accurate and reliable navigational aids; probably the same way a Private Pilot appreciates nav aids when flying an instrument approach in IFR conditions.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#55 2018-05-06 18:40:01

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,726

Re: GPS system for Mars?

With all the press we get mixed informations from headlines: Elon Musk’s SpaceX is using a powerful rocket technology. NASA advisers say it could put lives at risk.

Concerns at NASA over the astronauts’ safety hit a high point when, in September 2016, a SpaceX Falcon 9 rocket blew up while it was being fueled ahead of an engine test.

SpaceX were looking to make their Falcon 9 rocket even more powerful, they came up with a creative idea — keep the propellant at super-cold temperatures to shrink its size, allowing them to pack more of it into the tanks.

NASA is requiring SpaceX and Boeing to meet a requirement that involves some complicated calculations: The chance of death can be no greater than 1 in every 270 flights.

Something we here know is that we take everything with a grain of salt and we make sound judgement on what can be and what is not....

This article was risk adversion to what could be a safety concern but only time will tell...

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#56 2018-05-06 18:54:35

Void
Member
Registered: 2011-12-29
Posts: 3,011

Re: GPS system for Mars?

I am butting into a place where I normally don't.

Ever since the flight of the falcon heavy, there has been rustling in the weeds against Elon Musk and now SpaceX.

They seem to indicate that the super chilled fuel and Oxygen are more dangerous.

It is a fine time to mention it now.  Why did they not think of it before the method was established as a practice?

Last edited by Void (2018-05-06 18:57:12)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#57 2018-05-06 19:50:17

kbd512
Moderator
Registered: 2015-01-02
Posts: 3,010

Re: GPS system for Mars?

Rob,

I'll respond to your commentary in a separate thread in "Not So Free Chat" to try to limit further thread drift.

GW,

The 1960's and 1970's were definitely the golden age for human space exploration, unfortunately we're never going back to what we used before and that's that.  The same applies to military aerospace.  The aerospace tech development from the 60's and 70's produced the forerunners of all modern technologies in use today.  Everything from digital avionics and flight control systems, advanced laser radar, laser ring gyros, cellular telephones and computer networks, navigation aids like GPS, extreme performance chemical rocket engines, advanced nuclear and ion in-space propulsion systems, advanced batteries like Lithium-Ion, the beginnings of closed-loop life support, and long duration human space flight experimentation all came from that era.  It's taken another half century of refinement to position ourselves to accept the challenge of sending humans to Mars with acceptable and manageable risks to the lives of those people.

My take on the use of GPS, of whatever flavor, on Mars is that if you build a port where you have multiple ships moving in close proximity to each other, then you have a harbor master (computer-controlled flight) and lighthouse (GPS) to tell the ships where to go.  If we're sporadically flinging robotic probes into a general area, then no such system is required.  Given the quantity of robotic probes delivered to Mars, as opposed to any other exploration targets, it's obvious at this point that interest in the planet is only growing.

Clark,

I don't believe that Louis is a troll, just an eternal optimist.  There's nothing wrong with optimism, as long as it's tempered with a healthy dose of reality.

GPS, laser or microwave, is the modern method for position fixing.  If precision navigation is required for Mars EDL and surface operations, then this is the technology set that must be developed and deployed to Mars.  The Mars 2020 rover will use laser navigation for EDL, so it's going to get tested on Mars before BFR is ready to fly.  All testing up to this point from lunar probes indicates that it provides the best possible result for the least mass and volume, therefore cost.  It's still experimental, but there is considerable investment on NASA's part to produce high speed data relays and extreme precision navigation systems.  This will enable several of SpaceX's BFR's to perform the Buck Rogers maneuver in close proximity to each other.

Oldfart1939,

I agree about the need for some pathfinder missions to make sure all of these things we think will work actually work when human lives are committed to the endeavor.  My take on this is that if BFR is going to be built, and there appears to be no stopping that now, then we use it as efficiently as possible.  That means several of these things get delivered to Mars and never return to Earth.  They go to and from Mars orbit once they're at Mars, but that's as far as they go.

We use Argon-fueled ion engines for sending humans and cargo to Mars because we can do that in an affordable and practical manner if artificial gravity and radiation protection are incorporated into the design of spacecraft that go to an from Mars, but never reenter.  The vehicles will refuel at Mars using Argon captured from the Martian atmosphere.  NASA spent tons of money on development of large solar arrays and high powered ion engines and now it's time to reap the rewards from those investments.  If we use modular purpose built vehicles for interplanetary transits, then whether the trip takes a month longer or not is immaterial.

The NASA / Aerojet-Rocketdyne X3 ion engine will complete testing in 2018, culminating in a full power 200kWe firing.  It's already surpassed 100kWe output and produced 5.4 Newtons of thrust in testing and that's a world record.  Computer flight simulation models show that when the power output level reaches 600kWe, corresponding to a cluster of three of these new X3 engines, the flight durations match the flight durations achievable with chemical propulsion.  Once that happens, using chemical propulsion to deliver payloads makes no sense and the argument over what propulsion method to use becomes a moot point in terms of the cost of using chemical propulsion.

If EMDrive microwave propulsion ever pans out then we keep using our solar arrays, but drop the ion engines and fuel tanks.  EMDrive is just a more efficient ion engine in terms of thrust produced and total mass, but still requires lots of electrical power.  Transit times are substantially reduced, but artificial gravity continues to ensure that the humans arrive ready to work.

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#58 2018-05-06 20:04:57

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,176

Re: GPS system for Mars?

The real trolls are coming out of the woodwork now - trying to stop the Space X mission to Mars - ULA, Boeing, NASA science geeks and all the rest...Their methods will become increasingly desperate and unfair over the next couple of years. Mars is moving into the politics zone and no one plays fair there.


SpaceNut wrote:

With all the press we get mixed informations from headlines: Elon Musk’s SpaceX is using a powerful rocket technology. NASA advisers say it could put lives at risk.

Concerns at NASA over the astronauts’ safety hit a high point when, in September 2016, a SpaceX Falcon 9 rocket blew up while it was being fueled ahead of an engine test.

SpaceX were looking to make their Falcon 9 rocket even more powerful, they came up with a creative idea — keep the propellant at super-cold temperatures to shrink its size, allowing them to pack more of it into the tanks.

NASA is requiring SpaceX and Boeing to meet a requirement that involves some complicated calculations: The chance of death can be no greater than 1 in every 270 flights.

Something we here know is that we take everything with a grain of salt and we make sound judgement on what can be and what is not....

This article was risk adversion to what could be a safety concern but only time will tell...


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#59 2018-05-06 20:40:37

kbd512
Moderator
Registered: 2015-01-02
Posts: 3,010

Re: GPS system for Mars?

Louis,

ULA and Boeing have no say-so over how SpaceX proceeds.  NASA has some say-so in the matter, but FAA has final authority regarding what flies and what doesn't, even when it comes to rockets NASA is developing.  FAA is not shy about overriding opinions that have no founding in flight history.  FAA is very apolitical in this process.  If it appears that a person or company has done due diligence and the basic concept has been proven to work acceptably well, then it typically defers to the hard work of the engineers responsible for the design of the aerospace vehicle and grants a flight permit.  It's entire reason for existence is to apply sound engineering principles to aviation experimentation, but to permit experimentation anyway because there's always a chance of failure.  Aviation can never advance if we're not permitted to make mistakes, even lethal mistakes, and FAA fully understands this.

There is no engineering argument as to why astronauts can't be aboard a vehicle while propellants are being loaded.  In fact, it's better that the astronauts are strapped in and the emergency escape system is armed and ready before propellants are loaded because at any point in time after loading begins, an explosion is always possible.  Most explosions occur while loading is in process, though, and that is the point that NASA and others have made.  SpaceX's point is that the emergency egress system was specifically designed to contend with the vehicle exploding because that is the point when escape is mandated.

Any vehicle loaded with hundreds to thousands of tons of energetic chemicals can explode at any moment in the right conditions, but the overwhelming majority of the time this does not happen.  If SpaceX was loading fluorine, hydrazine, or some other exotic propellant that's even more inherently unstable than standard rocket propellants like LOX / LH2 / RP-1 / LCH4, then NASA might have a valid experience-based point to make that draws upon the considerable pool of worldwide rocketry accidents.

Anytime you're aboard a rocket, you're playing with fire (literally) and the potential to get burned is always there.

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#60 2018-05-06 22:55:58

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 5,821
Website

Re: GPS system for Mars?

Oldfart1939 wrote:

I believe it was a big mistake on part of SpaceX to abandon the Red Dragon missions(s). A successful retropropulsive landing could have achieved many things discussed here on this thread as well as many others.

I always thought pure retropropulsive landing was very risky. Russian Soyuz uses a parachute, then retro-rockets for soft touch-down. New Shepard capsule by Blue Origin uses the same system. Dragon has a parachute, why not use it? I think NASA would accept that. Wasn't it NASA that rejected retropropulsive landing? Boeing's CST-100 Starliner uses parachutes and airbags. I believe NASA wants their first mission to splashdown on water too.

Last edited by RobertDyck (2018-05-06 22:59:19)

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#61 2018-05-06 23:43:38

Oldfart1939
Member
Registered: 2016-11-26
Posts: 1,780

Re: GPS system for Mars?

Retropropulsive landings weren't the problem according to NASA; it was the landing legs that extended from the heat shield that they didn't like. NASA thought that compromised the HS structural integrity during reentry.

NASA: "The old ways are the best ways." Not.

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#62 2018-05-07 00:54:36

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 5,821
Website

Re: GPS system for Mars?

I heard that. But Shuttle had wheel well doors in the heat shield. And Gemini 2 was an unmanned test of the Gemini B spacecraft, intended for Manned Orbiting Laboratory (MOL). MOL was cancelled, but the Gemini spacecraft worked. It had a man-size hole in the heat shield, to allow crew to climb into MOL. The test flight was to test that the hole didn't compromise structural integrity. Again, it worked. Flight was January 1965. So I discount that.

Gemini B heat shield. Click image for Wikipedia article on MOL.
194px-Gemini-B_Heat_Shield.jpg

Last edited by RobertDyck (2018-05-07 00:57:46)

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#63 2018-05-07 01:39:39

Oldfart1939
Member
Registered: 2016-11-26
Posts: 1,780

Re: GPS system for Mars?

Robert-
I view the stance of NASA as looking for an "excuse," because the "old ways are the best ways." Again, it's risk avoidance.

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#64 2018-05-07 16:13:21

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,717
Website

Re: GPS system for Mars?

Louis joined these forums some 3 years earlier than me,  according to the authorship data on the posts.  He finds some of the damnedest things published on the internet.  Stuff I generally don't have time to go look for.  I'm not about to discourage him from doing that. 

As for NASA not wanting to to do Red Dragon,  whether because of retropropulsion,  or landing legs through heat shields,  what you are looking at there is lame excuses.  Sometimes the desperation behind them is apparent,  sometimes not so much.  But it really does point to the "dry empty skull" problem,  doesn't it?  Or else the "let's not embarrass our favored contractors" problem.  Which is really just another form of the "dry empty skull" problem.

Loading propellants into a rocket is dangerous.  About as dangerous as riding that same rocket.  Doesn't really matter if the crew is aboard or not,  especially if the design has pad abort capability.  "Dry empty skull" problem. 

I still maintain we need a precision satellite positioning system of some kind in order to make pinpoint landings.  And we need a pathfinder on the sites proposed for BFS "rough-field" landings to verify smoothness,  soil bearing strength,  and presence of buried ice.  It takes all three to make "mission 1" a much higher probability of success.  No doubt about it.

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#65 2018-05-07 18:41:50

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,726

Re: GPS system for Mars?

Yes Loius was a member over on Red Colony at the time as well just prior to the web sites for Mars were all hacked it would seem and or crashed real hard. Some have not come back and we were very lucky to have soem of the content in backup to be able to get the site back up after quite the initial efforts by Josh....

I am hoping that the ride along satellites with Insight are a size and cost that we can send lots of them to mars at a low cost to make.
Will lookup more on them and dual post some of the content where it applies.

The Red Dragon was a new ship of which I think the version for the ISS is not the same but simular for manned flight. It will be something to what in terms of it being used for other destinations.

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#66 2018-05-07 19:48:24

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,726

Re: GPS system for Mars?

A hunting I have gone and here is what I have found about the pair of stow aways that will arrive at mars in November..

Satellites WALL-E and EVE Are Hitching a Ride to Mars, Twin briefcase-sized satellites will pop out after launch and accompany InSight, providing a communications link

5-4-2018-cubesats-insight.jpg

Similar in size to a briefcase or large cereal box, the satellites with pop out from the rocket's upper stage following liftoff and hightail it to Mars, right behind InSight.

It will be the first time little cube-shaped satellites, CubeSats as they're known, set sail for deep space. The journey will span 6 1/2 months and 300 million miles.

A brief look at the $18.5 million experiment tagging along with InSight:

Once free from the rocket's upper stage following liftoff, WALL-E and EVE will trail a few thousand miles behind InSight en route to Mars. The two mini spacecraft will also be a few thousand milesapart from one another. That's to prevent any collisions or even close calls. While that may seem far apart, it's actually fairly close by space standards, according to Brian Clement, an engineer on the project at NASA's Jet Propulsion Laboratory in Pasadena, California. While InSight will be stopping at Mars on Nov. 26, WALL-E and EVE will zoom past the planet from about 2,200 miles out.

All has gone as planned as NASA's Tiny, Mars-Bound Satellites Have Successfully Signaled Home

Called MarCO-A and MarCO-B, the tiny machines have already passed the first important milestone in their groundbreaking mission to the Red Planet.

When MarCO-A and MarCO-B arrive at Mars later this year, they’ll be the smallest machines to ever visit another planet.

Known as nanosatellites, these devices weigh a mere 30 pounds each, and measure just 14.4 inches by 9.5 inches by 4.6 inches when packed into a rocket’s cargo hold.

Once at Mars, the tiny satellites will provide a communications link with stations on Earth as InSight makes its perilous entry to the surface.

The goal of the CubeSats is a proof-of-concept mission to test the viability of sending small satellites to the outer reaches of the Solar System.

NASA scientists are using the mission to understand if and how CubeSats can work in deep space, testing their endurance and navigational abilities. Should all go well, NASA can start to think about similar missions to other Solar System bodies, such as the outer gas planets and possibly even the Kuiper Belt.

Solar will not work out there thou as that will require nuclear powered systems to make it a possibility.

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#67 2019-03-17 19:57:36

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,726

Re: GPS system for Mars?

Cubesat's should have atopic all alone but the success of these show we can do more with them...

NASA's latest cubesat candidates include a solar sail test

Nasa plans to launch as small payloads scheduled in 2020, 2021 and 2022.

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#68 2019-09-03 21:27:08

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,726

Re: GPS system for Mars?

Tiny satellites that will pave the way to Luna

Mini- and micro-satellites, a technology that has matured over the past 40 years to make space science considerably cheaper, have therefore come forward as a great option. In more recent years, we have even started to consider using nanosatellite platforms - such as CubeSats. These are tiny satellites weighing a few tens of kilograms where a standard platform has been developed onto which different instruments can be fitted.

Using these sat for finding what we will need and mapping where it is.

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#69 2019-12-02 21:16:02

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,726

Re: GPS system for Mars?

A landing beacon is simular to NASA develops second-generation search and rescue beacon technology

Of course I suggested that we could use cubesat's for the gps as we are not looking for double digit lifetimes as a decade woul ber plenty and then replace as these are cheap to make... we also saw a pair of them aid Insight with landing...

NASA selects trisept to support new round of cubesat missions

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#70 2019-12-03 19:46:17

louis
Member
From: UK
Registered: 2008-03-24
Posts: 5,176

Re: GPS system for Mars?

Thanks for all your hard work on saving and archiving, Spacenut!

SpaceNut wrote:

Yes Loius was a member over on Red Colony at the time as well just prior to the web sites for Mars were all hacked it would seem and or crashed real hard. Some have not come back and we were very lucky to have soem of the content in backup to be able to get the site back up after quite the initial efforts by Josh....

I am hoping that the ride along satellites with Insight are a size and cost that we can send lots of them to mars at a low cost to make.
Will lookup more on them and dual post some of the content where it applies.

The Red Dragon was a new ship of which I think the version for the ISS is not the same but simular for manned flight. It will be something to what in terms of it being used for other destinations.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#71 2019-12-03 20:41:49

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,726

Re: GPS system for Mars?

Louis you will enjoy this memory from 2003 front page articles
https://web.archive.org/web/20030203232 … olony.com/

This one is from 2005
https://web.archive.org/web/20051023235 … olony.com/

Remember the forums
https://web.archive.org/web/20060705194 … com/forum/

I miss the site and it seems that the domain is up for sale....

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#72 Yesterday 14:51:10

Oldfart1939
Member
Registered: 2016-11-26
Posts: 1,780

Re: GPS system for Mars?

Any other private pilot here? What I was suggesting was something akin to the WAAS system at almost every airport in country--if instrument landing rated/certified.
WAAS = Wide Area Augmentation System, which is symbiotic with GPS satellites. These are transponders which the properly instrumented airplane can utilize under zero-zero visibility. This is how the big airliners do autoland at major airports; not always as smooooooth as a good pilot can do, but always on the ground, on the centerline of the runway, and everyone still alive. Most USA airports currently mandate autolandings be done to smooth traffic flows.

Brief description of the system: several transmitters/beacons/transponders are located at the field and is precisely linked to GPS constellation. These reduce the error in approach to inches instead of yards. This is undoubtedly what SS will need in order to land SAFELY  on Mars.

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