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I wonder if we have on FR someone familiar enough with aerodynamic design to roughly estimate the upward force ("lift"*) on a pop-up camper being towed at 60 mph if the camper is tilted, front up...

SmartBird is an ultralight but powerful flight model with excellent aerodynamic qualities and extreme agility. With SmartBird, Festo has succeeded in deciphering the flight of birds - one of the oldest dreams of humankind.

Breaking curveball too good to be true Curveballs curve and fastballs go really fast, but new research suggests that no pitcher can make a curveball “break” or a fastball “rise.”

In the cockpit of the sleek, black aircraft slung underneath the wing of the B-52 bomber, my interphone crackles. "Ah, Robert, it’s a lovely morning," says Jack Allavie, the commander of the B-52 launch aircraft. "Yes it is, Jack," I respond while running through the preflight checklist for our July 17, 1962 mission. The North American Aircraft X-15 was designed to investigate flight at hypersonic (Mach 5-plus) speeds and extremely high altitudes, and the effects of aerodynamic heating on aircraft surfaces. It was the first aircraft to fly Mach 4, Mach 5, and Mach 6—and I had the good fortune...

The U.S. Air Force is gearing up for the first of four planned test flights of a hypersonic aircraft designed to operate for much longer durations and cover far greater distances than previous platforms of its type. The maiden flight of the X-51 Waverider aircraft — the first U.S. hypersonic vehicle to fly in six years — is scheduled to take place later in March. Boeing Defense, Space & Security Systems of St. Louis has been developing the aircraft since 2003 on behalf of the Air Force Research Laboratory and Defense Advanced Research Projects Agency. The missile-shaped X-51 will be...

The U.S. Air Force is gearing up for the first of four planned test flights of a hypersonic aircraft designed to operate for much longer durations and cover far greater distances than previous platforms of its type. The maiden flight of the X-51 Waverider aircraft — the first U.S. hypersonic vehicle to fly in six years — is scheduled to take place later in March. Boeing Defense, Space & Security Systems of St. Louis has been developing the aircraft since 2003 on behalf of the Air Force Research Laboratory and Defense Advanced Research Projects Agency. The missile-shaped X-51 will be...

On January 29, the prototype Russian fifth generation Prospective Aircraft Complex of Frontline Aviation (PAK FA) “T-50” finally completed a successful 45 minute test flight in Komsomolsk-na-Amurye. The stealth multirole fighter was developed by OKB Sukhoi (experimental design bureau) to replace MiG-29 and Su-27’s and is reportedly analogous to the US F-22 (Raptor). Mikhail Pogosyan, Sukhoi’s Director-General, praised the aircraft’s maiden flight, saying that it marked a breakthrough for the Russian aviation industry (Rossiya 24, January 29). Indeed, the reported technical specifications of the aircraft are impressive. It has a maximum supersonic cruising speed of 2,100 kilometers (km) per hour,...

The latest Russian fighter design, the T-50, made its first flight on January 29th. Also called PAK FA (Prospective Aviation System of Frontline Aviation), or T-50, it’s a radical development of the Su-27/30/35 series of aircraft. The 47 minute test flight was done without the new engines designed for the T-50. Russia has always had problems with high performance jet engines, and those woes continue. "Evolving" an aircraft design, in this case, the Su-27, is a Russian custom. New models of a base design are given new names. The U.S. also does this, but keeps the original name. The Russian...

U.S. defence giant Lockheed Martin hopes to sign an agreement with Israel on its F-35 fighter jet by the end of the year, and targets 75 to 100 jets for the deal, an executive said on Friday. "Israel is extremely interested and we very much hope that we will make a deal with Israel for F-35s this year," Patrick Dewar, a corporate vice president at Lockheed Martin told Reuters at the Bahrain air show. "When we talk about Israel, somewhere between 75 and 100 jets," he said, when asked to estimate the size of the market for F-35s. Dewar also...

A testing delay for the F-35 program will prompt an increase in the per-unit cost of the stealthy single-engine fighter “for a period,” says the U.S. Air Force chief of staff, Gen. Norton Schwartz. Schwartz says the boost will not, however, be enough to breach requirements under the Nunn-McCurdy reporting law, which triggers a mandatory Pentagon review of alternatives and notification of Congress in cases of a significant cost and schedule overrun. The chief says the delay, which he only described as not lasting “multiple years,” was necessary. Government officials have indicated that completing testing could take up to 30...

For some time, NASA has focused much of its limited aeronautics research budget on the blended wing-body configuration, believing it has the best chance of meeting its aggressive environmental targets for commercial aircraft entering development after 2025. These include reductions exceeding 70% in fuel burn, 75% in emissions and 71dB in airport noise compared to today's airliners. Now the agency is broadening its search to include other alternatives to the ubiquitous tube-and-wing layout. And one of those is the truss-braced wing (TBW), or strut-braced wing (SBW), a concept that allows a substantially longer span for significantly higher lift-to-drag (L/D) ratio....

Science Daily — The maneuverability of a bat in flight makes even Harry Potter’s quidditch performance look downright clumsy. While many people may be content to simply watch these aerial acrobats in wonder, Kenneth Breuer and Sharon Swartz are determined to understand the detailed aerodynamics of bat flight – and ultimately the evolutionary path that created it. They have taken a major step toward that goal by combining high-resolution, three-dimensional video recordings with precise measurements of the wake field generated by the bats’ wing movements. Their study, published in the journal Bioinspiration and Biomimetics, marks the first such measurements made...

Mimicking humpback whale flippers may improve airplane wing design DURHAM, N.C. -- Wind tunnel tests of scale-model humpback whale flippers have revealed that the scalloped, bumpy flipper is a more efficient wing design than is currently used by the aeronautics industry on airplanes. The tests show that bump-ridged flippers do not stall as quickly and produce more lift and less drag than comparably sized sleek flippers. The tests were reported by biomechanicist Frank Fish of West Chester University, Penn., fluid dynamics engineer Laurens Howle of the Pratt School of Engineering at Duke University and David Miklosovic and Mark Murray at...

Underwater Gliders Take Flight to New DepthsBy Andrew Bridges The Associated PressPublished: Nov 23, 2003 SAN DIEGO (AP) - A century after the Wright Brothers first took to the skies, the world of flight is pushing to new depths. Researchers are perfecting innovative gliders that can swoop and soar on journeys covering hundreds of miles and lasting for weeks - all deep beneath the ocean waves. The fledgling technology, barely a decade old, has already produced robotic submarine gliders that move slowly, with the nimbleness of a blimp. Now next-generation gliders are being developed to fly just as gracefully as...