Tom Adams Posted July 21, 2006 Share Posted July 21, 2006 My company (Gulfstream Aerospace) released some info that I thought you might find interesting. Our Quiet Spike technology could possibly be the next major leap in aircraft technology equivalent to the move from piston driven propulsion to jet propulsion. I've had the chance to go through our Sonic Boom Simulator and can tell you that the attenuation of the sonic boom due to the Quiet Spike is incredibly dramatic. The predicted sound pressure level being lower than a group of kids playing on a playground! Enjoy...... GULFSTREAM AEROSPACE TO TEST PATENTED SPIKE FOR<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /> CONTROLLING AND REDUCING SONIC BOOM ON NASA F-15 Flight Testing will Verify Structural Integrity of Multi-segmented, Articulating, Advanced Composite Material Quiet Spike Gulfstream Aerospace, a wholly owned subsidiary of General Dynamics (NYSE: GD), this summer will test the structural integrity of its patented telescopic Quiet Spike sonic boom mitigator on a NASA F-15 flight test bed. The company designed and developed the Quiet Spike as a means of controlling and reducing the sonic boom caused by an aircraft breaking the sound barrier. A series of flights, to be conducted in late July and early August at the <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />NASA Dryden Flight Research Center in the California Mojave Desert, will validate the structural integrity of the multi-segmented, articulating Quiet Spike. Made of advanced composite materials, the Quiet Spike weighs some 470 pounds and extends from 14 feet in subsonic flight to 24 feet in supersonic flight. Since March 2004, when Gulfstream was awarded a patent for the Quiet Spike, the device has been through extensive ground testing, including wind-tunnel testing, to arrive at the point where it could be installed on an F-15B aircraft and flown. The F-15B is capable of flying at speeds in excess of Mach 2.0, or two times the speed of sound. From the outset it has been understood that the sonic boom must be reduced to acceptable levels before consideration could be given to developing a prototype quiet supersonic jet, said Pres Henne, senior vice president, programs, engineering and test, Gulfstream Aerospace. These tests are just a few in a series of activities which must be undertaken to prove to numerous regulatory agencies and environmental groups, both at home and abroad, that supersonic flight over land is achievable in a way that will significantly reduce the impact of the sonic boom on people and on the environment. It is only one step, but a very important step, for all of us. Once the Quiet Spike has proven to be structurally sound, it can be incorporated with confidence onto advanced low-boom configuration aircraft to further control and mitigate adverse acoustic impacts of supersonic flight. The Quiet Spike will be an important means of changing the traditional N-wave sonic boom into smooth and more rounded pressure waves, shaped roughly like a sine wave or a sideways S. This change in the wave shape results in a softer sound that is quieter than the Concorde sonic boom by a factor of 10,000. GULFSTREAM FIRST BUSINESS JET MANUFACTURER TO OFFER SYNTHETIC VISION COCKPIT Synthetic Vision-Primary Flight Display (SV-PFD) Augments Safety of Gulfstream Jets Gulfstream Aerospace will be the first business-jet manufacturer to offer synthetic vision technology for new production and in-service aircraft. Gulfstream will offer its Synthetic Vision Primary Flight Display (SV-PFD) as an optional upgrade to current operators of PlaneView®-equipped Gulfstream G550, G500, G450 and G350 business jet models. Following certification by the Federal Aviation Administration (FAA) in 2007, Gulfstream also will begin offering the optional upgrade to future customers and current customers awaiting completion of their new PlaneView-equipped aircraft. With its real-time, pilots view of the world beyond the cockpit windshield, SV-PFD increases a pilots ability to accurately interpret the depth and texture of terrain, obstacles, runways and approaches, said Pres Henne, senior vice president, programs, engineering and test, Gulfstream. It is the next logical step in display technology, resulting in faster and more accurate tactical flight decisions by pilots and ultimately increased safety of flight. Gulfstream SV-PFD imaging is a dramatic enhancement to the PlaneView flight displays. Innovative technology developed with Honeywell, and a pilot-centered design approach, with an emphasis on integration with the proven PlaneView capability, have improved on the two dimensional, blue-over-brown image. SV-PFD features a three-dimensional color image of terrain overlaid with the PFD instrument readings. With SV-PFD, instrument readings are arranged on the screen to create a large view area for terrain. Combining previously certified terrain data from Honeywells Enhanced Ground Proximity Warning System (EGPWS) with obstacle data, and using a new state-of-the-art graphics processor, SV-PFD accurately depicts terrain, obstacles, runways and approaches at locations throughout the world. Maintaining the tradition of PlaneView and building on Gulfstreams participation in NASAs GVSITE Synthetic Vision research program, SV-PFD includes both traditional and Head-Up Display (HUD) symbology. Symbols such as attitude, altitude, airspeed, bank and steering cues, flight path marker, Terrain Awareness and Warning System (TAWS) alerts, and Traffic alert Collision Avoidance System (TCAS) all remain the same. The new HUD-like symbols include a flight path marker, a path-based flight director runway outline and a runway lead-in line. SV-PFDs flight guidance symbology and truer terrain images provide pilots information in terms of terrain distance and horizontal and vertical bearing, Henne added. This increased level of awareness means safer operations and is especially beneficial near airports and in mountainous areas. According to the FAA, 91 percent of General Aviation fatal air accidents in 2005 were caused by a pilots loss of control of the aircraft, including during approach, landing and flying into terrain. Quote Link to comment Share on other sites More sharing options...
Joe Shmoe Posted July 21, 2006 Share Posted July 21, 2006 What exactly is it that causes the "boom"? Quote Link to comment Share on other sites More sharing options...
jacksonbart Posted July 21, 2006 Share Posted July 21, 2006 exceeding the speed of sound Quote Link to comment Share on other sites More sharing options...
Doc Robin Posted July 21, 2006 Share Posted July 21, 2006 Cutting edge technology; sure hope everything goes well. Later Bill Quote Link to comment Share on other sites More sharing options...
JohnA Posted July 21, 2006 Share Posted July 21, 2006 What exactly is it that causes the "boom"? The boom is a cone-shaped wave of highly compressed air generated by the leading edges of supersonic objects. It is dragged along the ground like a cape, but sounds like an explosion as it passed across your ears. It sounds like that because your ears are subjected to a sudden increase in pressure followed by a sudden decrease. Often you will hear 2 booms; one from the nose or wing and one from the tail (BaBOOM!). Quote Link to comment Share on other sites More sharing options...
Tom Adams Posted July 21, 2006 Author Share Posted July 21, 2006 What exactly is it that causes the "boom"? Hey Joe - The following does a pretty decent job of explaining it in layman's terms: http://en.wikipedia.org/wiki/Sonic_boom What's critical to the sound level of the sonic boom is the so-called N-wave. It's called that because when you graph the pressure rise up to the point of Mach 1 it is very steep, almost vertical. Once the transition occurs to Mach 1, the pressure wave builds & peaks again. The resulting graph looks like an 'N' instead of your typical smooth sine wave. And it's this N-wave that gives a sonic boom that distinct ba - BOOMP sound. IOW, there isn't a single "boom" but rather two distint "booms". Those that have heard this understands what I'm trying to say. I hope it makes sense to you. If not call me and I'll make the sound over the phone - but only once! LOL.....[] Anyhow........ The Quiet Spike essentially modifies this N-wave to smooth out the wave form. So, you still get a "boom" from the resulting transition to Mach 1, it's just that the "boom" has a longer dwell time which the human ear percieves as a lower sound level. It's kinda like hitting a snare drum that results in a db level of say 80 and then striking a kettle drum that also makes the meter read 80db. To the ear, it sounds like the kettle drum is quieter. Pretty cool, huh? Tom Quote Link to comment Share on other sites More sharing options...
ranjith Posted July 21, 2006 Share Posted July 21, 2006 Tom, thats HUGE... wouldn't that technology (if integrated into all future aircrafts) mean that you have supersonic flights over populated areas and not just over the atlantic and such? By implication it should make air travel faster than ever before by leaps and bounds. Quote Link to comment Share on other sites More sharing options...
Joe Shmoe Posted July 21, 2006 Share Posted July 21, 2006 Thanks Thomas... so what your company did was somehow modify the design/airflow characteristics of the jet to achieve this? I think I got it now... Quote Link to comment Share on other sites More sharing options...
3dzapper Posted July 21, 2006 Share Posted July 21, 2006 I kind of miss the double boom of the Concorde offshore of Cape Cod. One off the nose another the wings. Here is a B2 breaking the sound barrier. The moist air of the sea compresses into visable vapor: another of an F-14: General Dynamics might be talking GulfStream but that boom has definite military capabilities. Rick Quote Link to comment Share on other sites More sharing options...
jorjen Posted July 21, 2006 Share Posted July 21, 2006 Man, amazing technology Tom. You have GOT to be proud as Hell to be associated with a company involved in such an advanced project. Mind boggling stuff, really. Quote Link to comment Share on other sites More sharing options...
Tom Adams Posted July 21, 2006 Author Share Posted July 21, 2006 Tom, thats HUGE... wouldn't that technology (if integrated into all future aircrafts) mean that you have supersonic flights over populated areas and not just over the atlantic and such? By implication it should make air travel faster than ever before by leaps and bounds. You hit the nail on the head. That's why Gulfstream (well, General Dynamics) has covered their bases by submitting and obtaining patents for all the various iterations of the design. So basically, if the FAA approves the design, we become the only company that can fly supersonic over land. We then follow up by obtaining the same exemptions from the European authorities as well as the various Asian authorities. And since we hold the patent rights, guess what the other players must do if they wish to compete? You got it, they must buy the rights. That's, of course, assuming we'd sell them. This is why I said that the Quiet Spike has the potential to completely change the face of General Aviation just as jet propulsion did. As for military application, I'm sure GD is looking at it, but the real emphasis here is being the first, and only, biz jet that can fly supersonic anywhere, anytime in the world. And believe me, there's plenty of rich mo' fo's out there that would gladly pony up the bucks so they can brag to their rich peeps that they have a biz jet that can kick *** in the speed department. Tom Quote Link to comment Share on other sites More sharing options...
j-malotky Posted July 22, 2006 Share Posted July 22, 2006 Very Interesting. Can't wait to see a demonstration of how it works. Maybe in a few more years at Oshkosh. JM Quote Link to comment Share on other sites More sharing options...
Jay481985 Posted July 22, 2006 Share Posted July 22, 2006 Tom, wow thats impressive, someone finally made it work. I remember work was being conducted and all the experiments were looking very good. Though that device seems a little big at 14-25 feet long for a plane that is only 50 feet long. I wonder how the drag co... is? Also would the plane that Gulfstream would like to build that reaches mach 1 or more be able to reach that speed without the need of afterburners or with? Can it be sustained throughout the flight or can only do sportatic bursts? Also does it need to be in any specific height/air density ratio to lose the sonic boom, I assume going mach 1 at sealevel is still a no no.... Anyways it sounds like a great idea, since the concorde's departure I find it sad that there are no commercial means to break the soundbarrier. I always like the ring of "faster than a speeding bullet" Quote Link to comment Share on other sites More sharing options...
oldbuckster Posted July 22, 2006 Share Posted July 22, 2006 Oh my, I thought this was about being a fan of the Jefferson Airplane...........................interesting thread, could speed up travel times, it's amasing that you can go that fast in the first place..........................Has the sound barrier ever been broken on land? I think it has, but I'm not sure..... Quote Link to comment Share on other sites More sharing options...
Jay481985 Posted July 22, 2006 Share Posted July 22, 2006 by land do you mean sealevel or by land just over it??? most airplanes are banished to go supersonic only in the ocean because the sonic boom causes windows to shatter and drywall to crack. The sr-71 went three times the speed of sound to have the record and it was over land. Quote Link to comment Share on other sites More sharing options...
Ray Garrison Posted July 22, 2006 Share Posted July 22, 2006 really cool Quote Link to comment Share on other sites More sharing options...
Moderators Travis In Austin Posted July 22, 2006 Moderators Share Posted July 22, 2006 Oh my, I thought this was about being a fan of the Jefferson Airplane...........................interesting thread, could speed up travel times, it's amasing that you can go that fast in the first place..........................Has the sound barrier ever been broken on land? I think it has, but I'm not sure..... What is the speed of sound at sea level. If it is 600 mph then it has been broken on land back in The Spirt of America, remember him and Craig Breedlove? It is in the Petersen Museum in Los Angeles, which I highly reccomend everyone check out if you are in LA if you have any appreciation at all for cars or motorcycles. Tom, When are you going to get us all a ride on a G5? Travis Quote Link to comment Share on other sites More sharing options...
Moderators Travis In Austin Posted July 22, 2006 Moderators Share Posted July 22, 2006 Oh my, I thought this was about being a fan of the Jefferson Airplane...........................interesting thread, could speed up travel times, it's amasing that you can go that fast in the first place..........................Has the sound barrier ever been broken on land? I think it has, but I'm not sure..... What is the speed of sound at sea level. If it is 600 mph then it has been broken on land back in The Spirt of America, remember him and Craig Breedlove? It is in the Petersen Museum in Los Angeles, which I highly reccomend everyone check out if you are in LA if you have any appreciation at all for cars or motorcycles. Tom, When are you going to get us all a ride on a G5? Travis Quote Link to comment Share on other sites More sharing options...
Jay481985 Posted July 22, 2006 Share Posted July 22, 2006 I believe sea level speed of sound is 732 mph.... sealevel has denser air meaning sound goes faster. The higher you go the less dense it is, hence the reduced speed of sound. Quote Link to comment Share on other sites More sharing options...
oldbuckster Posted July 22, 2006 Share Posted July 22, 2006 Isn't the speed of sound the same not matter at sea level, or in the air? I'm asking, I'm not sure? Getting rid of the sonic blast would open up a whole new way of travel.........Spirit of America broke the land speed record, did it also break the speed of sound? Quote Link to comment Share on other sites More sharing options...
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