Sunday, June 14, 2009

Mind-blowing Engineering

This video is not aviation related but worth watching I hope every one would like it.

This incredible machine was built as a collaborative effort between The Robert M. Trammell Music Conservatory and the Sharon Wick School of Engineering at the University of Iowa . Amazingly, 97% of the machine's components came from John Deere Industries who make tractors, and Irrigation Equipment of Bancroft, Iowa, manufacturers of farm equipment. For sceptics who think this is computer animation, It took the team a combined 13,029 hours of set-up, alignment, calibration, and tuning before filming this video. The machine is now on display in Iowa in the Matthew Gerhard Alumni Hall at the University and is already slated to be donated to the Smithsonian.

Ten Worst airplanes

By Chuck Squatriglia
July 7, 2008
In the 105 years since the Wright Brothers took to the air, dreamers, engineers and aviation buffs have designed every kind of airplane imaginable in a never-ending quest to fly higher, faster or further. Some were innovative, some were beautiful and some even made history. Others, well, let's just say they must have looked good on paper.
Here's a tribute to the 10 worst ever that surely looked better on paper. (Photos below).

Tupolev TU- 144

1.The Concorde gets all the love, but Russia's Tupolev TU-144 was the first supersonic transport and the only commercial plane to exceed Mach 2. The "Concordski" was fast but plagued by bad luck. Three crashes -- including a dramatic mid-air breakup during the 1973 Paris Air Show -- relegated it largely to a lifetime delivering mail. It was mothballed in 1985 but briefly brought back a few years later as a research plane.

B.O.A.C de Havilland Comet

2.The Comet was the premiere commercial jet airliner and a landmark in British aeronautics when it first flew in 1949. Today it's better known for its atrocious safety record. Of the 114 Comets built, 13 were involved in fatal accidents, most of them attributed to design flaws and metal fatigue.

Hughes H-4 Hercules
3.The “Spruce Goose” was either a brilliant aircraft years ahead of its time or the biggest government boondoggle ever. By far the largest aircraft ever conceived -- its wingspan was 319 feet -- the Spruce Goose was intended to be a military transport plane. But it wasn't finished until well after World War II ended, rendering it both obsolete and irrelevant. It only flew once.

LWS-4 Zubr

4.The Polish Zubr was as useless as it was ugly. Not only was it incapable of flying with the landing gear retracted, the airframe was so highly stressed the plane could disintegrate without warning. If that wasn't enough, it couldn't take off with a payload much heavier than a few cartons of cigarettes. The Polish Air Force had a few in its fleet during World War II, but none of them saw combat.

Christmas Bullet

5.Cool name, lousy plane. Dr. William Christmas didn't know the first thing about planes when he designed one for the U.S. Army Signal Corps, and it showed. He didn't think the plane needed wing struts, so of course they fell off during the plane's maiden flight in 1918.

Beechcraft Starship
6.With its carbon-composite construction, unique design and rearward-facing turboprop engines, the Starship was a groundbreaking aircraft. But it was slow, difficult to fly and a bear to maintain. It took to the air in 1989, but Beechcraft only sold a few of the 53 it built.

Hiller VZ-1
7.The Hiller VZ-1 hovercraft must have looked good on paper, because it sure didn't look good in the air. The idea was simple -- a fan provides lift and the pilot steers by shifting his weight. The Defense Department loved it until it saw the Pawnee in flight. It was good for just 16 mph and it tended to be uncontrollable. The project was killed in the late 1950s.

A-12 Avenger II
8.Defense Department projects are famous for cost overruns, and General Dynamic’s flying wing bomber was a doozy. The Flying Dorito was the most troubled of the stealth aircraft projects the Pentagon embraced during the 1980s, experiencing problems with its radar systems and use of composite materials. When the projected cost of each plane ballooned to $165 million, a Secretary of Defense named Dick Cheney killed it in 1991.

Royal Aircraft B.E.2
9.With its anemic engine, poor maneuverability and gunner blocking the pilot's view, the British B.E. 2 was doomed from the start. German pilots had no problem shooting them down during the First World War, making it just about useless as a fighter. It had no problems against German Zeppelins, though, so the plane lived out its days attacking them instead.

Boeing XB 15
10.The XB 15 was the largest plane ever built in the United States until the Spruce Goose came along. The heavy bomber was so massive it had passageways in the wings and bunks for the crew. But big planes need big engines and no one made one big enough to give the XB any kind of speed for its maiden flight in 1937. The plane maxed out at 200 mph, and the U.S. Army Air Corps killed the project. The only XB ever built saw duty as a cargo plane in the Caribbean during World War II.

Friday, June 12, 2009

Future Technology and Aircraft Types

The following discussion is based on a presentation by Ilan Kroo entitled, Reinventing the

Airplane: New Concepts for Flight in the 21st Century.

When we think about what may appear in future aircraft designs, we might look at recent history. The look may be frightening. From first appearances, anyway, nothing has happened in the last 40 years!
There are many causes of this apparent stagnation. The first is the enormous economic risk involved. Along with the investment risk, there is a liability risk which is of especially great concern to U.S. manufacturers of small aircraft. One might also argue that the commercial aircraft manufacturers are not doing too badly, so why argue with success and do something new? These issues are discussed in the previous section on the origins of aircraft.Because of the development of new technologies or processes, or because new roles and missions appear for aircraft, we expect that aircraft will indeed change. Most new aircraft will change in evolutionary ways, but more revolutionary ideas are possible too.This section will discuss several aspects of future aircraft including the following:

1.Improving the modern airplane
2.New configurations
3.New roles and requirements

Improving the Modern Airplane
Breakthroughs in many fields have provided evolutionary improvements in performance. Although the aircraft configuration looks similar, reductions in cost by nearly a factor of 3 since the 707 have been achieved through improvements in aerodynamics, structures and materials, control systems, and (primarily) propulsion technology. Some of these areas are described in the following sections.

Active Controls

Active flight control can be used in many ways, ranging from the relatively simple angle of attack limiting found on airplanes such as the Boeing 727, to maneuver and gust load control investigated early with L-1011 aircraft, to more recent applications on the Airbus and 777 aircraft for stability augmentation.
Reduced structural loads permit larger spans for a given structural weight and thus a lower induced drag. As we will see, a 10% reduction in maneuver bending load can be translated into a 3% span increase without increasing wing weight. This produces about a 6% reduction in induced drag.Reduced stability requirements permit smaller tail surfaces or reduced trim loads which often provide both drag and weight reductions.
Such systems may also enable new configuration concepts, although even when applied to conventional designs, improvements in performance are achievable. In addition to performance advantages the use of these systems may be suggested for reasons of reliability, improved safety or ride quality, and reduced pilot workload, although some of the advantages are arguable.

New Airfoil Concepts
Airfoil design has improved dramatically in the past 40 years, from the transonic "peaky" sections used on aircraft in the 60's and 70's to the more aggressive supercritical sections used on today's aircraft.
Continuing progress in airfoil design is likely in the next few years, due in part to advances in viscous computational capabilities. One example of an emerging area in airfoil design is the constructive use of separation. The examples below show the divergent trailing edge section developed for the MD-11 and a cross-section of the Aerobie, a flying ring toy that uses this unusual section to enhance the ring's stability.
Flow Near Trailing Edge of DTE Airfoil and Aerobie Cross-Section

Flow Control
Subtle manipulation of aircraft aerodynamics, principally the wing and fuselage boundary layers, can be used to increase performance and provide control. From laminar flow control, which seeks to reduce drag by maintaining extensive runs of laminar flow, to vortex flow control (through blowing or small vortex generators), and more recent concepts using MEMS devices or synthetic jets, the concept of controlling aerodynamic flows by making small changes in the right way is a major area of aerodynamic research. Although some of the more unusual concepts (including active control of turbulence) are far from practical realization, vortex control and hybrid laminar flow control are more likely possibilities.

Structural materials and design concepts are evolving rapidly. Despite the conservative approach taken by commercial airlines, composite materials are finally finding their way into a larger fraction of the aircraft structure. At the moment composite materials are used in empennage primary structure on commercial transports and on the small ATR-72 outer wing boxes, but it is expected that in the next 10-20 years the airlines and the FAA will be more ready to adopt this technology.
New materials and processes are critical for high speed aircraft, UAV's, and military aircraft, but even for subsonic applications concepts such as stitched resin film infusion (RFI) are beginning to make cost-competitive composite applications more believable.

Propulsion is the area in which most evolutionary progress has been made in the last few decades and which will continue to improve the economics of aircraft. Very high efficiency, unbelievably large turbines are continuing to evolve, while low cost small turbine engines may well revolutionize small aircraft design in the next 20 years. Interest in very clean, low noise engines is growing for aircraft ranging from commuters and regional jets to supersonic transports.

Multidisciplinary Optimization
In addition to advances in disciplinary technologies, improved methods for integrating discipline-based design into a better system are being developed. The field of multidisciplinary optimization permits detailed analyses and design methods in several disciplines to be combined to best advantage for the system as a whole.
The figure here shows the problem with sequential optimization of a design in individual disciplines. If the aerodynamics group assumes a certain structural design and optimizes the design with respect to aerodynamic design variables (corresponding to horizontal motion in the conceptual plot shown on the right), then the structures group finds the best design (in the vertical degree of freedom), and this process is repeated, we arrive at a converged solution, but one that is not the best solution. Conventional trade studies in 1 or 2 or several parameters are fine, but when hundreds or thousands of design degrees of freedom are available, the use of more formal optimization methods are necessary.
Although a specific technology may provide a certain drag savings, the advantages may be amplified by exploiting these savings in a re-optimized design. The figure to the right shows how an aircraft was redesigned to incorporate active control technologies. While the reduced static margin provides small performance gains, the re-designed aircraft provides many times that advantage. Some typical estimates for fuel savings associated with "advanced" technologies are given below. Note that these are sometimes optimistic, and cannot be simply added together.

1.Active Control .............10%

2.Composites ..................20%

3.Laminar Flow ..............10%

4.Improved Wing ...........10%

5.Propulsion ...................20%

Total ..............................70%

New Configuration Concepts
Apart from evolutionary improvements in conventional aircraft, revolutionary changes are possible when the "rules" are changed. This is possible when the configuration concept iteself is changed and when new roles or requirements are introduced.
The following images give some idea of the range of concepts that have been studied over the past few years, some of which are currently being pursued by NASA and industry.

Blended Wing Body

The BWB design is intended to improve airplane efficiency through a major change in the airframe configuration. The thick centerbody accommodates passengers and cargo without the extra wetted area and weight of a fuselage. Orginally designed as a very large aircraft with as many as 800 passengers, versions of the BWB has been designed with as few as 250 passengers

and more conventional twin, podded engines.

Joined Wing

The joined wing design was developed principally by Dr. Julian Wolkovitch in the 1980's as an efficient structural arrangement in which the horizontal tail was used as a sturcural support for the main wing as well as a stabilizing surface. It is currently being considered for application to high altitiude long endurance UAVs.

Oblique Flying Wing

One of the most unusual concepts for passenger flight is the oblique wing, studied by Robert T. Jones at NASA from 1945 through the 1990s. Theoretical considerations suggest that the concept is well suited to low drag supersonic flight, while providing a structurally efficient means of achieving variable geometry.

New Roles and Requirements
In addition to new configuration ideas, new roles and requirements for aircrafrt may lead to new aircraft concepts. Some of these are summarized below.
Pacific Rim Travel
As global commerce continues to increase, the need for passenger and cargo transportation grows as well. Many have speculated that growth in pacific rim travel may be the impetus for high speed aircraft development. The figure above suggests how the time required for flight from Los Angeles to Tokyo varies with cruise Mach number. (The somewhat facetious Mach 8 aircraft requires extra time to cool off before passengers can deplane.)

Supersonic transportation (Boeing High Speed Civil Transport Concept)

Ground Effect Cargo Tranport Concept

Vehicles designed for missions other than carrying passengers include military aircraft with new constraints on radar detection (low observables), very high altitude aircraft, such as the Helios solar powered aircraft intended for atmospheric science and earth observation studies, and vehicles such as the Proteus, designed as a communications platform.

Low Observables (B2 Bomber)

Autonomous Air Vehicles (Pathfinder: a prototype for Helios solar UAV)

Halo Autonomous Air Vehicle for Communications Services (an AeroSat)

Finally a new class of air vehicles intended to provide lower cost access to space is under study. The near-term future of such designs depends on the economic health of the commercial space enterprise and it presently appears that these concepts are not likely to be seen soon.

Access to Space


1. Improved understanding and analysis capabilities permit continued improvement in aircraft designs
2. Exploiting new technologies can change the rules of thegame,permitting very different solution
3. New objectives and constraints may require unconventional configurations
4. Future progress requires unprecedented communication among aircraft designers, scientists, and computational specialists

Unusual aircraft (part 1)

Airbus, Shell begin alternate fuel research

Airbus, Shell begin alternate fuel research
By: Thierry Dubois
Airbus and Shell recently made the first ever commercial flight using liquid fuel processed from gas when an A380 airliner flew from Filton in the UK to the airframer’s Toulouse, France headquarters. The flight marked the start of a program to evaluate the environmental impact of alternative fuels in the airline market.One of the A380’s four Rolls-Royce Trent 900 engines was powered by a blend of Shell’s gas-to-liquid (GTL) fuel and standard jet-A. The other three engines burned jet-A. The aircraft’s segregated fuel tanks made it well suited for engine shutdown and relight tests.For Airbus, the three-hour flight was the first step in its efforts to evaluate viable and sustainable alternative fuels. It believes that GTL fuel–which promises less impact on air quality and more efficient fuel burn–could be available at certain locations to make it a practical alternative fuel for commercial aviation in the short term. The manufacturer believes that development of GTL will support future second generation bio-fuels, which are not presently available in sufficient commercial quantities. Airbus has committed itself to studying viable second generation bio-fuels when they become available.With global prices of petroleum on the rise, scientists are striving to bring second-generation biofuels from the research stage to full production. First-generation biofuels–which airlines together with aircraft and engine manufacturers are close to flight-testing–cut overall carbon dioxide emissions because their feedstock plants absorb CO2, but they still have major environmental drawbacks. First-generation fuels can be seen as wasteful in that they use only part of the plant (cereal grains or beetroot, for example).By contrast, second-generation biofuels are created using plants in their entirety, including straw, wood and so on. Also, the range of raw materials available to create second-generation fuels is larger and more types of plants can be used, as well as waste such as wood chips.The greater efficiency of second-generation biofuels is seen as an answer to at least one major concern. Green groups have been challenging the use of huge land surfaces to produce fuel rather than food, which has already raised the price of some basic food, such as corn. Using the entire plant is viewed as much better from the perspective of those who believe the primary role of agriculture as a food source for humans shouldn’t be compromised. Using vegetable waste is one way to solve the problem, but collecting waste–such as wood chips and straw– can be challenging. Forestry and farm waste is highly scattered, and building big plants to transform large quantities of waste would involve a lot of transportation to collect and consolidate it. Another alternative would have the biofuels process relying instead on small, local units. The first generation of biofuels also has raised concerns about biodiversity. “Is it reasonable to replace rain forest with sugar cane or cereal fields?” a senior executive at a major U.S. airline recently asked rhetorically. Environmental experts see retaining biodiversity–the living fabric that covers the earth–as urgent an issue as global warming. Second-generation biofuels, if made from waste, do not affect biodiversity, but the problem remains if they are made from purpose-grown plants.Three kinds of processes are under development. The first–biochemical–yields sugar and then ethanol but it is not well suited to aviation, according to Xavier Montagne, deputy scientific director of IFP, a French research institute on oil and energy. “Ethanol contains 33 percent less energy than today’s jet fuel,” Montagne, explained to AIN. Energy density is critical in aviation, where weight and volume are enemies of efficiency. In addition, ethanol’s flash point is too low. While jet fuel has a specification for 100 degrees F, the flash point for ethanol is just 59 to 64 degrees F.The second process, called biomass to liquid (BtL), is thermochemical. Biomass is first transformed into a synthetic gas, then the Fischer-Tropsch (F-T) process converts the gas into liquid hydrocarbons. The final product can be used to make a fuel that is very close to (and, in some respects, even better than) current jet fuel.“The first part of the process is the most challenging,” Montagne said. The second part, the F-T process, is well known now. However, further performance improvement is needed in F-T facilities, Montagne added.In terms of greenhouse emissions, second-generation biofuels would perform appreciably better than those further along in development. First-gen biofuels can save up to 70 percent of CO2 emissions over oil-based fuels (measured through the so-called well-to-wheel approach), but savings of 90 percent can be achieved with BtL, according to Montagne.Another second-gen biofuel is hydrotreated vegetable oil (HVO). For example, vegetable oil made from lipid algae, if hydrotreated, yields a fuel that is close to that obtained with BtL. Their main characteristics, including flash point, are consistent with aviation requirements. Their energy content is a bit lower than today’s jet-A fuel if measured per volume, but it is greater if measured per weight.Last June, engine maker CFM International said it was evaluating alternative fuels made using biomass. But some still speculate whether the benefits of the second-generation biofuels are enough. “Should we spend millions on biofuel research and production, while IATA has assigned the industry the challenge to be carbon-free in 2050?” asked the same skeptical U.S. airline executive

Thursday, June 11, 2009

The World's First Flying Hotel

"The Hotelicopter features 18 luxuriously-appointed rooms for adrenaline junkies seeking a truly unique and memorable travel experience. Each soundproofed room is equipped with a queen-sized bed, fine linens, a mini-bar, coffee machine, wireless internet access, and all the luxurious appointments you'd expect from a flying five star hotel. Room service is available one hour after liftoff and prior to landing." The Hotelicopter is due to fly maiden journey this summer(June 26th) with an undisclosed price....If you have interesting? There is three fly tour.

Dimensions Length: 42 m (137 ft)
Height: 28m (91 ft)
Maximum Takeoff Weight: 105850 kg (232,870 lb)
Maximum speed: 255 km/h (137 kt) (158 miles/h)
Cruising speed: 237 km/h (127 kt) (147 miles/h)
Original Mi Range: 515 km (320 mi)
Our augmented Mi Range - 1,296 km (700 mi)

Wednesday, June 10, 2009

A tip from an anonymous commenter points us to this announcement from Evergreen Aviation."EVERGREEN SUPERTANKER READY TO FIGHT WILDFIRES The B747 Supertanker is certified to fly by Interagency Air Tanker BoardMcMinnville, Ore.—Evergreen International Aviation’s B747 Supertanker won certification for operation this season after receiving its interim approval letter from the Interagency Air Tanker Board. The aircraft also received its Supplemental Type Certificate from the Federal Aviation Administration (FAA) in November 2008. It is now available to assist world firefighting agencies during the 2009 season and beyond. The award is unique because the Supertanker has an 8:1 drop ratio compared to that of all other current firefighting aircraft, meaning the Supertanker will forever change the way wildland fires are fought. The plane is the first of a fleet designed to accommodate the needs of U.S. and International private and public agencies.The Supertanker showed impressive results during the U.S. Forest Service administered grid tests. From high, medium and low coverage levels, the Supertanker showed it provides quality, consistent retardant line construction. The cutting-edge aircraft proved it belongs on the front line, from the onset, to fight wildfire day and night. The uniformed pattern of the Supertanker drops, and its ability, in a single flight, for split loads at multiple coverage levels, gives agencies an incredibly versatile firefighting tool.The multi-role B747 Supertanker is the largest tanker aircraft available today. With a payload of more than 20,000 gallons and a response time of 600 mph, it has more than eight times the drop capability and twice the speed of any other federal air tanker currently fighting fires. The Supertanker’s patented pressurized system has the capability to disperse product at high pressure for an overwhelming response, or disperse at the speed of falling rain in a single or several segmented drops. This pressurized system will also allow for drops at higher altitudes, creating a significant safety buffer and enabling the Supertanker to fight fires during the day and at night, when they are most vulnerable. It also offers a significant value for saving homes, natural resources, and most importantly, lives. When employed properly, the Supertanker has the capability to save the governments billions of dollars in fire suppression, natural resource losses, tourism, and rehabilitation costs every year.Evergreen International Aviation, which has more than 70 years of firefighting experience and more than one million hours of large aircraft operating experience, has invested five years and $50 million of its own funding to develop this next generation of firefighting aircraft.The Supertanker program will continue to grow and advance its capabilities. On the firefighting front, operations of the Supertanker will expand to Western Europe, Australia and Brazil. The aircraft will be available to provide service to international governments, as well as private industry. The next endeavor is to prove the vehicle as a solution for oil spills, decontamination of biological/chemical poisoning and radiation knock down. With this diverse range of qualifications, the Supertanker will go on protecting valuable resources for generations to come.