Starship Asterisk*

kingernie wrote:To compare this to the grand achievement of the Wright brothers is insulting.

kingernie wrote:And the payload was what?

To compare this to the grand achievement of the Wright brothers is insulting. The brothers received NO taxpayer supplied monies in their initial development of viable heavier than air craft.

*Thirty-three years in aerospace engineering at The Aerospace Corporation. The opinions expressed are my own, and I am not representing the corporation.

Chris Peterson wrote:

saturn2 wrote:
In the space the solar wind move the spacecrafts of solar sails.

Solar wind is a minor contributor to the propulsion generated by solar sails. The force comes mainly from radiation pressure.

http://en.wikipedia.org/wiki/Solar_sail wrote:
<<There are two sources of solar forces: radiation pressure, and solar wind. Radiation pressure is much stronger than wind pressure. Both of these forces are small and decrease with the inverse square distance from the Sun.

In 1924, the Russian space engineer Friedrich Zander proposed that, since light provides a small amount of thrust, this effect could be used as a form of space propulsion requiring no fuel. Einstein proposed (and experiments confirm) that photons have a momentum p=E/c; therefore, each light photon absorbed by or reflecting from a surface exerts a small amount of radiation pressure. This results in forces of about 4570 mN/km² (~ 1 pound of force per square kilometer of sail) for absorbing surfaces perpendicular to the radiation in Earth orbit, and twice as much if the radiation is reflected.

Charged particles from the solar wind are able to point the ion tails of comets away from the Sun. The solar wind averages 6.7 billion tons per hour at 520 km/s with "slow" low energy coronal ejections reaching 400 km/s and "fast," higher energy ejections averaging 750 km/s. At the distance of the Earth, this results in average solar wind pressure of 3.4 mN/km², and is three orders of magnitude less than the photonic radiation pressure. Still the solar wind dominates many phenomena because its interaction cross section with gases and charged particles is about 10⁹ times larger than that of the photons.>>

http://en.wikipedia.org/wiki/Dawn_%28spacecraft%29 wrote:
<<The Dawn spacecraft (now orbiting Vesta) is propelled by three xenon ion thrusters which produce a thrust of 90 mN.>>

Chris Peterson wrote:

drollere wrote:
relevance to astronomy: 0%
chances similar technology will be deployed on mars within a century: 0%

I disagree. Assuming we continue to explore Mars, I think the likelihood of solar powered aircraft on the planet is quite high.

http://marsairplane.larc.nasa.gov/platform.html wrote:

The ARES full-scale and half-scale flight test vehicles.

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Chris Peterson wrote:
We are also likely to see fleets of aircraft similar to this cruising our own atmosphere, as Earth observation tools- which is certainly relevant to astronomy.

saturn2 wrote:In the space the solar wind move the spacecrafts of solar sails.

drollere wrote:relevance to astronomy: 0%
chances similar technology will be deployed on mars within a century: 0%

biddie67 wrote:
Such an unwieldy looking machine - I'm glad that it managed to reach the altitude it did but it sure doesn't look as though it can handle any atmospheric turbulance, storms, etc.

nstahl wrote:
They'd better get Martian weather forecasting down well. It doesn't look like it would survive in one of their windstorms, unless maybe it could get above it or at least above the vorticity, shears and downdrafts.

http://en.wikipedia.org/wiki/Helios_Prototype wrote:

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Bruegel's Landscape with the Fall of Icarus (ca. 1558), famous for relegating the fall to a scarcely noticed event in the background

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<<On June 26, 2003, the Helios Prototype broke up and fell into the Pacific Ocean about ten miles (16 km) west of the Hawaiian Island Kauai during a remotely piloted systems checkout flight in preparation for an endurance test scheduled for the following month.

On the morning of the accident, weather forecasts indicated that conditions were inside the acceptable envelope, although during the preflight go/no-go review, the weather forecaster gave it a "very marginal GO." One of the primary concerns was a pair of wind shear zones off the island's coast. After a delayed take off, due to the failure of the winds to shift as predicted, Helios spent more time than expected flying through a zone of low-level turbulence on the lee side of Kauai, because it was climbing slower than normal, since it had to contend with cloud shadows and the resultant reduction in solar power.

As the aircraft climbed through 2,800 feet (850 m), according to the subsequent mishap investigation report, "At about 30 minutes into the flight, the aircraft encountered turbulence and morphed into an unexpected, persistent, high dihedral configuration. As a result of the persistent high dihedral, the aircraft became unstable in a very divergent pitch mode in which the airspeed excursions from the nominal flight speed about doubled every cycle of the oscillation. The aircraft’s design airspeed was subsequently exceeded and the resulting high dynamic pressures caused the wing leading edge secondary structure on the outer wing panels to fail and the solar cells and skin on the upper surface of the wing to rip off. The aircraft impacted the ocean within the confines of the PMRF test range and was destroyed. Most of the vehicle structure was recovered except the hydrogen–air fuel cell pod and two of the ten engines, which sank into the ocean."

The investigation report identified a two-part root cause of the accident:

"Lack of adequate analysis methods led to an inaccurate risk assessment of the effects of configuration changes leading to an inappropriate decision to fly an aircraft configuration highly sensitive to disturbances."

"Configuration changes to the aircraft, driven by programmatic and technological constraints, altered the aircraft from a spanloader to a highly point-loaded mass distribution on the same structure significantly reducing design robustness and margins of safety.">>

Guest wrote:At a cost to taxpayers of .... ?????

NASA needs to start printing that below its logo.

Helios was intended as a technology demonstrator, but in the extremely thin air 30,000 meters above Earth's surface, the flight of Helios also approached conditions for winged flight in the atmosphere of Mars.]

Davmkris wrote:
Are the distances [sic] as stated correct? 3,000 meters is believable at about 10,000 feet.
But 30,000 meters puts it well above 100,000 feet. For real?

http://en.wikipedia.org/wiki/Flight_altitude_record wrote:
Fixed-wing propeller driven aircraft altitude records

Code: Select all

Year 	Altitude 	Person 	Aircraft 	Power
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1903 	3 m 		Wilbur Wright, Orville Wright 	Wright Flyer 	
1906 	4 m 		Alberto Santos-Dumont 	14-bis 	
1908 	110 m 		Wilbur Wright 	Biplane 	
1909 	920 m 		Louis Paulhan 	Farman 	
1910 	1,269 m 	Louis Paulhan 	Farman 	
1910 	1,403 m 	Walter Brookins 	Wright biplane 	
1910 	2,582 m 	Ralph Johnstone 	Wright biplane 	
1915 	3,640 m 	Joseph Eugene Carberry 	 ? 	
1920 	10,093 m 	Major Rudolf Schroeder 	LUSAC-11 	
1921 	10,518 m 	Lieutenant John Arthur Macready 	LUSAC-11 	
1930 	13,158 m 	Lieutenant Apollo Soucek, USN 	Wright Apache 	
1932 	13,404 m 	Cyril Unwins 	Vickers Vespa 	
1933 	13,661 m 	Gustave Lemoine 	Potez 50 	
1934 	14,433 m 	Renato Donati 	Caproni Ca.113 	
1936 	15,230 m 	Squadron Leader Francis Ronald Swain 	Bristol Type 138 	
1938 	16,440 m 	M. J. Adam 	Bristol Type 138 	
1938 	17,083 m 	Lieutenant Colonel Mario Pezzi 	Caproni Ca.161 	manned  record to date	
2001 	29.524 km 	NASA Helios HP01 	 	solar-electric aircraft - record for non-rocket plane

http://en.wikipedia.org/wiki/Mario_Pezzi_%28aviator%29 wrote:

- The conquest of the world record height - October 22, 1938

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- The device a Caproni 161 - Air which has been achieved the world record height of piston aircraft, a record still unbeaten (17.083m)

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<<Mario Pezzi (1898-1968) was an Italian aviator known worldwide for his flight in which he achieved greater height than any other pilot in a propeller-powered airplane.

The future lieutenant general was born November 9, 1898. He had one brother, Enrico, who also grew up to be a General in the Italian Air Force. Mario joined the Infantry in October 1917, and the next year earned the rank of second lieutenant. He received his pilot's license in 1926. The next year he became part of the General Staff, rising to Cabinet of the Defense Ministry in 1931.

On May 7, 1937, Maj. Mario Pezzi took off from the Guidonia-Montecelio base on a Caproni Ca161 aircraft powered by a 14 cyl. double stellar engine supercharged by a double centrifugal 750 hp compressor. Piloting this aircraft he climbed to 15,655 m. Pezzi wore a special electrically heated pressurized suit and an airtight helmet, just like a modern astronaut. In the Caproni hangars in the meantime work went on ceaselessly to produce a new version of the aircraft, the Ca161bis designed by engineer Verduzio. Its cockpit embedded an air-tight shell, the first one to be built in the history of flight. The great expectations on this machine were soon fulfilled: on October 22, 1938, Pezzi attained a new world record of altitude in a propeller-driven, piston-engined aircraft (17,083 m), record still unbeaten today.

Transferred to the command of the East African Air Force, he commanded the base of Dire Dawa in 1941 and was appointed Chief of Staff of East Africa. He was taken prisoner at Amba Alagi on 20 May 1941. After the Sept. 8 switch to the south and in December 1943 assumed command of Unity Air operate until February 1945. In September 1948 he was appointed Director General of the staff Military Air Force. From June 1950 to February 1955 he was head of Cabinet Minister and then Secretary General of the Air. Pezzi is rightly considered an aeronautics and astronautics pioneer in Italy not only for his altitude records: he was the man who chose Luigi Broglio to lead the ITAF Ammunition Research Unit, responsible for rockets and missiles research, leading the way to future space exploration in Italy. He died in Rome on August 26, 1967.

Davmkris wrote:Are the distances as stated correct? 3,000 meters is believable at about 10,000 feet. But 30,000 meters puts it well above 100,000 feet. For real?

2001 August 14 96,863 ft 29.524 km Unmanned NASA Helios HP01 propeller solar-electric aircraft - record for non-rocket plane

Guest wrote:At a cost to taxpayers of .... ?????