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For SpaceNut ...
There did not appear to be a topic dedicated to collection of news/insights/reports about lighter than air (atmosphere) aircraft
There ** are ** posts about such vehicles scattered throughout the forum.
This topic is set up for anyone who might wish to collect some of those posts in a single location.
I am particularly interested in seeing updates on the British "Bums" vehicle. It was developed in the United States and then transferred to Britain, where it has made a couple test flights, including one that ended with the nose plowing into the countryside at a modest pace.
The design featured two side-by-side gas envelopes, and lots of engines for steering and for attitude control.
I'd like to see it succeed in the real world, and would appreciate anyone reporting if they happen across updates.
A recent discussion about how to move large and bulky structures from factory to end site is the impetus for creation of this new topic.
Lighter-than-air aircraft would be ideal for moving such structures, if issues of stability and dealing with weather can be solved.
(th)
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For lighter-than-air, weather is always the "killer" issue. Nearly every blimp or dirigible loss all the way back to WW1 traces in one way or another to weather, even the Hindenburg. Only a few were shot down.
There's winds, there's lightning strikes, and there's static electricity building up and arcing to cause fires (Hindenburg). But especially winds: the Macon, the Los Angeles, and many others.
When I was young, I used to see some military dirigibles and blimps flying around (US Navy stuff). They were still common in the 1950's. Not so much in the 1960's. Just the Goodyear blimps at the football games.
GW
Last edited by GW Johnson (2021-09-28 12:01:26)
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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The blimp in question is, IIRC, slightly heavier than air, and relies upon thrust and/or forward momentum generating aerodynamic lift to ameliorate some of the control issues of true lighter than air blimps / dirigibles. I could see blimps carrying bulky but light cargo in fair weather (package transfer between Amazon warehouses, faster than road travel but with similar fuel burn, being point-to-point and not dependent upon local road traffic conditions, but only just), possibly hanging wind turbine blades, and serving as low-speed military mass transport for troops or oversized cargo, since so much less fuel is required than jet aircraft reliant upon aerodynamic lift and high speeds for flight. Load distribution for the type of blimp in question is still very critical for maintaining positive control over the vehicle, since it's essentially a very large / very-high-aspect low-speed wing.
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For kbd512 re #3
Thanks for your assessment of the potential of 21st Century lighter than air aircraft.
The web page at the link below indicates the company is in no hurry...
https://www.designboom.com/technology/l … 9-13-2021/
2025 is the current target date for passenger service.
My impression is that a lighter-than-air vehicle may be as difficult to fly as the B1/B2 bombers .... It is possible that modern computer controls might be able to overcome the difficulties that GW Johnson listed.
The issue of dealing with atmosphere (as pointed out by both GW Johnson and kbd512) is challenging, but it may be possible to deal with atmosphere using modern control techniques..
The ** real ** test would be to send one of these out as a Hurricane Tracker.
Military aircraft are speciallly fitted with suitable engines and propellers to deal with the inside of hurricane walls.
I would expect a lighter-than-air version of such a vehicle would have to go with the flow of the eye wall, while crabbing toward the eye.
Still, that is an interesting challenge for the engineers.
(th)
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Well you just added mass for the electrical need so unless it doubles as a structural need then its going to get heavier...
https://eijournal.com/news/industry-ins … challenges
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The current hurricane hunter aircraft are all Navy P-3's. Those are modified and refurbished 1950-vintage turboprop airliners called Lockheed Electra-2. It's the same engines and props on the P-3 as were on the Electra-2 (which I rode many times).
They had to solve a wing spar cracking problem in the 1960's to serve as airliners in the 1960's and early 70's, until jets took over. The "fix" must have worked, because the P-3's no longer shed wings, even when flying into hurricanes. There's not a one of these airframes less than 60 years old.
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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For Gw Johnson re #6
Thanks for the background on the hurricane hunter aircraft! The Weather Channel often shows lengthy video of the crew operating these sturdy aircraft during hurricane season. Somewhere along the line, in watching one of those videos, I picked up the impression the propellers are designed for the mission.
They do not look like ordinary commercial propellers, but instead have a much deeper structure and more pronounced curvature.
If you happen to have run across any information about them, I'd be happy to see it, even though (as often happens) we hve drifted slightly off topic.
If a lighter-than-air vehicle ** is ** able to perform the hurricane hunter mission, I would imagine the propellers would be modeled on the ones used by the P-3's.
Update at 13:51 local time .... (after post by GW Johnson)
SearchTerm:propeller paddle wheel design for turboprop engines ... see GW Johnson below this post
SearchTerm:Paddle wheel propeller for hurricane hunter aircraft
(th)
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Those are just wide "paddle" blades. Some versions of the C-130 had them, too. They were pretty common on the large turboprop aircraft. The greater blade area raised disk solidity, letting it absorb more power for a given diameter. Those turboprop engines were a whole lot more powerful than the recip engines they replaced, pound for pound. I think the Canadair 215-415 family of fire-fighting seaplanes has similar engines and propellers.
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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For lighter-than-air, weather is always the "killer" issue. Nearly every blimp or dirigible loss all the way back to WW1 traces in one way or another to weather, even the Hindenburg. Only a few were shot down.
There's winds, there's lightning strikes, and there's static electricity building up and arcing to cause fires (Hindenburg). But especially winds: the Macon, the Los Angeles, and many others.
When I was young, I used to see some military dirigibles and blimps flying around (US Navy stuff). They were still common in the 1950's. Not so much in the 1960's. Just the Goodyear blimps at the football games.
GW
One of my Grandmother's old friends, died several years back at over a hundred years old. I spoke to her shortly before she went into a nursing home. She had lived on the North Kent marshes all of her life and as a little girl she remembered seeing a Zeppelin flying up the Thames towards London. It is amazing how much has changed in 100 years.
Rigid airships rely upon non-pressurised gas cells containing hydrogen or helium to produce lift. These are tied at various points to a surrounding an aluminium alloy frame, which provides rigidity and maintains the shape of the ship. The frame is shrouded by an outer fabric cover. They have the advantage that they can be aerodynamic, with a low drag coefficient and don't distort when flying into the wind. But there were a lot of problems at the time due to materials limitations. Hydrogen is the most well known problem. Whilst the Americans used helium, for mass usage of the airship there really isn't any alternative to hydrogen. Helium is simply not abundant enough for more than a few proof of concept vehicles. Hydrogen can be vented from gas cells when they reach pressure height and simply topped up at the beginning of each journey. Helium must be conserved and expensively purified. No other gas can provide sufficient lift to be useful. So hydrogen it must be.
A bigger problem was that the aluminium frame had relatively high dead weight which consumed a lot of the static lift. This prompted attempts to reduce design factors, that ultimately led to the failure of many airships due to metal fatigue. This is how the Macron met its end. The British R101 attempted to substitute aluminium with high-strength steel. This reduced the fatigue problem but left the ship with too much structural weight to really be practical as anything other than a demonstration ship. The poor state of materials science in the 1930s, introduced a lot of problems that were intractable at the time. Polymers were new and not readily available. The outer covers of airships were made of cotton, as were the gas cells. This lost strength when wet and also tended to rot, making it unsuitable for an exterior cover that had to stand up to wind loadings. The gas cell were lined with Gold Beaters Skin, made from the intestinal linings of cattle. This reduced hydrogen leakage, but became brittle and leaked as it aged.
The R101 disaster occurred during a flight from England to India, during a stormy night. The wind ripped open the outer cover (which had rotted) and when pushed hydrogen out of the fwd gas cells, leading to a sudden loss of lift. The ship impacted the ground and caught fire when the diesel engines were pushed into body of the ship, igniting the gas cells.
The Hindenburg fire was caused when a bracing cable snapped during a sharp turn coming in to land. The cable slashed open a gas cell, releasing hydrogen which was then ignited by St Elmos fire (static electricity) on the outer casing when the ship was earthed to the ground.
Hydrogen filled rigid airships could make a limited come back as a means of passenger transportation as fossil fuels deplete. As a medium range transportation option, they compare to rail in terms of energy efficiency. Modern polymers, maraging steels, carbon and glass fibres, would all be useful in making the frames, gas cells and outer cover stronger and safer. The more intractable problem is low speed. Realistically, airships have a speed limit of 100mph, which is reduced substantially when the wind is against them. Low speed is an economic killer, because it means fewer passenger miles per year. An airship that is six times slower than a 747 therefore has a tough economic problem to overcome. They could usefully provide regional transportation over Europe or internal flights in North America. They do not require runways and can land on unimproved terrain. British efforts perfected the mooring tower.
The problem with using airships for trans-Atlantic travel is that typical crossing times for the Hindenburg were 48 hours. If people are on an aircraft that long, they want sleeping facilities, dining facilities and space to stretch their legs. That all adds up to a huge weight burden that would make a trans Atlantic airship flight considerably more expensive than Concord and about 15 times slower. A 747 gets there faster for less money. But if you needed to fly from London to Paris, say, or New York to Washington, a technologically upgraded rigid airship could do the job.
Not a workable option at all on Mars. No rigid airship could ever be light enough in the thin Martian atmosphere. However, high tensile polymer balloons filled with hydrogen, could be useful tools for exploring Mars. A one or two man team, equipped with electric motor bikes, could use a balloon to carry them to different locations on the planet, using the wind. No propulsion or fuel need be carried. Buoyancy could be adjusted by adding and venting hydrogen. The balloon need not be pressurised, but would need to be strong enough to resist buoyant forces.
Last edited by Calliban (2021-09-30 14:17:53)
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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Flying on Mars using some kind of Aircraft, Helicopter, Dirigibles or Balloons this discussion is back in the socila media news with JPL NASA's Ingenuity Helicopter with Mystery Cloth Debris Stuck to Its Leg?
A Mars aircraft is a vehicle capable of sustaining powered flight in the atmosphere of Mars.
Ingenuity Mars helicopter soars on 32nd flight
https://www.space.com/mars-helicopter-i … -flight-32
The USA with JPL NASA was first to fly on Mars, Ingenuity, nicknamed Ginny, is a robotic coaxial rotor helicopter operating on Mars as part of NASA's Mars 2020 mission along with Perseverance Rover, no other craft has yet to fly on Mars.
Sky-Sailor was a concept for a robotic aircraft with embedded solar cells on its wings, conceived in 2004 by the Swiss.
https://www.newscientist.com/article/mg … n-on-mars/
Most aerobot concepts were based on aerostats, primarily balloons, but occasionally airships. Flying above obstructions in the winds, a balloon could explore large regions of a planet in detail for relatively low cost. Airplanes for planetary exploration were also proposed.
The Russian Soviets during the days of the USSR had a Vega program, two balloon aerobots were designed to float at 54 km (34 mi) from the surface, in the most active layer of the Venusian cloud system. A cooperative effort among the Soviet Union and Austria, Bulgaria, France, Hungary, the German Democratic Republic, Poland, Czechoslovakia, and the Federal Republic of Germany to explore Comets and the planet Venus, it seems to be a separate mission to the overall Venus exploration of the Soviet Venera program.
NASA's concept for the Aerial Regional-scale Environmental Survey (ARES) was a proposal by NASA's Langley Research Center to build a robotic, rocket-powered airplane that would fly one mile above the surface of Mars.
https://www.nasa.gov/offices/ocio/ittal … rNASA.html
Another spaceplane Aerial Vehicle for In situ and Airborne Titan Reconnaissance an idea developed in 2011 by a team of scientists at the University of Idaho. Development was suspended indefinitely and the original design called for a 120 kg (260 lb) airplane powered by an advanced Stirling radioisotope generator. http://www.universetoday.com/92286/avia … for-titan/
On another world Titan, closer to the nature of a Planet than a Moon, Dragonfly will fy. Dragonfly a planned spacecraft robotic NASA mission, which will send a robotic rotorcraft to the surface of Titan, it will expand upon the Cassini mission, Dragonfly will study and explore the largest Moon of the Saturn system.
Some other news items
Giant balloon to float through Martian atmosphere
http://new.www.esa.int/Enabling_Support … atmosphere
Back in 2001
'jimharris submitted a bunch of links about flying on Mars'
https://science.slashdot.org/story/01/1 … ng-on-mars
It's a beautiful challenge - how to fly in a situation where everything you "know" about flight is wrong.
Martian Balloons
https://scienceblogs.com/principles/200 … n-balloons
old news from 1999
A Zeppelin for Mars exploration proposed by the students at Alpbach Summer School 1999
https://sci.esa.int/web/mars-express/-/ … chool-1999
Students at the annual Alpbach Summer School on Space Research and Technology proposed the use of a Zeppelin as a highly versatile vehicle to explore Mars. Space scientists so far had concentrated their efforts on rovers, balloons or planes - i.e. systems that are bound to the surface, free-flying but not steerable or too fast for detailed local investigations.
The new idea of using a Zeppelin provides three-dimensional steering and a choice between sejourning at a given, interesting place and traveling for surveying the landscape or to go to another location. A Zepplin is specially useful to study the so-called Mars dichotomy, a seven kilometer high wall, which gives access for the study of many geological layers, which otherwise could only be studied by deep Martian drilling.
Old new mars forums discussion
'Hindenburg'
https://newmars.com/forums/viewtopic.php?id=936
Last edited by Mars_B4_Moon (2022-10-04 06:03:48)
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TARS or Tethered Aerostat Radar System
U.S. Customs and Border Protection (CBP) assumed responsibility the Tethered Aerostat Radar System (TARS) project and its funding since fiscal year 2014.
pdf
https://obamawhitehouse.archives.gov/si … ummary.pdf
Sky Dew or Tal Shamayim is a high altitude missile defense aerostat used by Israel Defence Forces
Balloons
safety issues?
Chilling moment man in hot air balloon admires view moments before falling 1,500ft to his death
https://www.mirror.co.uk/news/world-new … r-32389176
It’s hard to catch MeV gamma-ray signals from space! But the Electron-Tracking Compton Camera could the savior!
https://www.isas.jaxa.jp/home/research- … 2024/0226/
Image of cosmic MeV gamma-ray observation using a scientific balloon. The ETCC is mounted inside the gondola. At an altitude of about 40 km, various background events such as cosmic rays, their secondary particles, and atmospheric gamma rays enter the detector.
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