ATO # 95 - February 4, 2000
QuestChats require pre-registration. Unless otherwise noted, registration is at: http://quest.arc.nasa.gov/aero/chats/#chatting Thursday, February 10, 2000 10 AM - 11 AM Pacific Aerospace Team Online QuestChat with Kelly McEntire Kelly McEntire manages a small group of mechanical, aerospace and structural engineers, responsible for supporting the aeropropulsion engineers (a.k.a., rocket scientists) in their lab. Read his biography at http://quest.nasa.gov/aero/team/mcentire.html Wednesday, February 16, 2000, 1:00 PM Regimes of Flight Chat with Steve Smith Steve Smith is an aerospace research engineer who studies how airplanes will perform at different speeds. Right now he's researching supersonic flight and he uses computers, wind tunnels and is build his own plane. Read his bio at http://quest.nasa.gov/aero/team/smith.html Thursday, March 2, 2000 10 AM - 11 AM Pacific Aerospace Team Online QuestChat with Earl Duque Earl Duque studies how air flows around, through, and under objects such as wings, propellers and aircraft vehicles. Read his biography at http://quest.nasa.gov/aero/team/duque.html
BLACK HISTORY MONTH CHAT SERIES
February is Black History Month. To celebrate, NASA Quest will host a series of QuestChats and forums with African American scientists and engineers who contribute their work in support of NASA's mission and goals. The schedule which may be added to over time can be found at http://quest.nasa.gov/qchats/special/mlk00/ Some of these are of special interest to Aerospace Team Online participants! Tuesday, February 8 - Thursday, February 10, 2000 Pacific Forum(questions not answered live during a three day period) with Julie Williams-Byrd Electronics Engineer/Aerospace Technologist, Langley Research Center Julie designs and builds lasers to investigate the makeup of the atmosphere. Read her biography at http://quest.nasa.gov/women/bios/jwb.html Tuesday, February 8, 2000, 9:00 AM Pacific Chat with Kim Hubbard, Computer Scientist Kim works on system engineering and software development. She has helped to network computers in space. Read her biography at http://quest.nasa.gov/women/bios/kh.html Thursday, February 24, 2000, 9 AM Pacific Chat with Aprille Ericsson-Jackson, Ph.D., Aerospace Engineer Aprille works on guidance, navigation and control, and design analysis at Goddard Space Flight Center Read her bio at http://quest.nasa.gov/space/frontiers/ericsson.html
NEW CONTENT Sneak preview the "Regimes of Flight" a new resource for teachers and students about flight at different speeds. This will be targeted for grades 4-8. You will find background material, lesson plans, chats and contests!! For more information see http://quest.nasa.gov/aero/events/regimes - - - - - - CONTESTS Regimes of Flight Class Mural Contest, Grades 4-8 January 25 - March 2,2000 Choose one regime of flight: low, medium, high, supersonic, or hypersonic. Classes submit a mural that visually depicts not only the definition and description of the category, but also visually depicts aircraft from that category (Note: Key word "visually" means no words). For more information: go to http://quest.nasa.gov/aero/events/regimes/contest.html
[Editors Note: For a change I sending a chat archive instead of a journal this week. I hope this will motivate some of you to join us in a chat this month. There's plenty of room for your questions! This chat was with Kelly McEntire. Read his bio at http://quest.nasa.gov/aero/team/mcentire.html ]
January 12, 1999 QUESTCHAT WITH KELLY MCENTIRE
Turbomachinery Branch Chief NASA Glenn Research Center, Cleveland, OH [ Oran/NASAChatHost - 5 - 09:28:57 ] Hello and welcome to today's Aerospace Team Online chat with Kelly McEntire from NASA Lewis Research Center. Kelly is involved in jet engine engine research. He manages a group of 12 engineers that turn the ideas of the groups' lab rocket scientists, also known as aeropropulsion researchers, into reality. All members of the team are involved in mechanical engineering and, as Kelly explains, the job of an engineer is to turn the ideas of today into the realities of tomorrow. [Ms.Metcalf/Yokayoschool-Ms.Metcalf/Yokayo] How are you making jet engines more powerful and fuel efficient? [ KellyMcEntire/GRC - 26 - 10:11:15 ] The thrust in today's research is not to make them more powerful, we already know who to do that. It is to make them quieter, faster, less pollution, and of course more fuel efficient. There are many ways that are being looked at to make engine more fuel efficient. I am a mechanical engineer, a chemical engineer could better answer that questions. Some ways that I am aware of are to make them burn hotter and to improve the way fuel is injected into the engine. [Ms.Metcalf/Yokayoschool-Ms.Metcalf/Yokayo] What new alloys make jet engines lighter? [ KellyMcEntire/GRC ] We are trying many different kinds of materials which include aluminum alloys and graphics composite materials. We must use alloys that have a high heat tolerance so they won't melt when the fuel burns. Higher temperature usually means more efficient enginers. [Ms.Metcalf/Yokayoschool-Ms.Metcalf/Yokayo] Have you had any problems with space engine designs? [ KellyMcEntire/GRC ] The biggest problem with space engine design is that you have to carry oxygen with you. Oxygen is heavy. The atmosphere up to a certain point has lots of oxygen already present, so we are trying to come up with an engine that will burn the oxygen from the air when its present so you don't have to carry the extra weight and once you get up so high there is not enough oxygen to help burn the fuel, it then uses it own that is carried on board. [Ms.Metcalf/Yokayoschool-Ms.Metcalf/Yokayo] Are you using any new types of fuel for spaceships? [ KellyMcEntire/GRC ] No, the basic fuels are still hydrogen and oxygen. A rocket engine burns about twice as much hydrogen as oxygen and so it takes much larger tanks to carry it. Hydrogen is also a gas so it has to be compressed or it would take up way too much room. The more we compress it the less room it takes up. We are trying to come up with ways to compress it more or as we call it to densify it. This will allow us to go further with the same size rocket ship. [kACEY-Mrs.Choate/ViennaGrade] Mrs.Choate/ViennaGrade In about 20 years from now, which planets do you think we could visit? [ KellyMcEntire/GRC ] I think we will visit Mars within the next 20 years. Today, we are trying to figure out how to send a rocket there. The problem is not can we do it? The problem is will the American taxpayers pay the 100's of billions of dollars it would take to get there? [Ms.Metcalf/Yokayoschool-Ms.Metcalf/Yokayo] How does computer technology aided in the design of the jet engine? [ KellyMcEntire/GRC ] Yes, we use computer aided design or CAD as we call it all the time. We use software packages call solid modelers that we design the engine with. We are able to see the engine in its entirety before we even build the first part. This helps us to avoid errors and helps us get it right the first time. [Ms.Metcalf/Yokayoschool-Ms.Metcalf/Yokayo] How high can a plane with a jet engine fly? [ KellyMcEntire/GRC ] I do now know for sure, but I think the upper reaches of the atmosphere where there is not enough oxygen to help burn fuel is at about 100,000 feet or about 20 miles. Specials engines can burn at higher altitudes. The oxygen gets thinner and thinner. [Ms.Metcalf/Yokayoschool-Ms.Metcalf/Yokayo] What are the frequent modes of failure in the jet engines? [ KellyMcEntire/GRC ] The failure mode that we are most concerned with is a blade in the rotor breaking off. These blades are spinning about about 15,000 revolutions per minutes or 15 Krpm. If ones breaks off, the centrifugal energy will propel it like a bullet. It can fly through into the cabin of the aircraft and kill someone or bring the whole aircraft down. [Dean-Mr.Richard/homeschool] What current project are you involved in? [ KellyMcEntire/GRC ] As a supervisor of a group of engineers, we work on many different projects. Each 1 or 2 engineers are working different projects. One of these projects is called High Speed Research or HSR. We are trying to develop an engine for the next generation Concord, except this time this aircraft would be used by everyone flying from LA to Tokyo or from New York to Toyko, etc. It would fly at 15000 mph. Another project is one to figure out why jet engines are so noisy. Believe it or not, we don't understand where all the noise comes from. If you have ever been at the end of a runway and heard a jet plane taking off you know how loud it is. Many airports around the world are making laws so planes can't make so much noise are certain times of the day, i.e. when people are trying to go to sleep. [Ms.Metcalf/Yokayoschool-Ms.Metcalf/Yokayo] What are the ups and downs with working with jet engines? [ KellyMcEntire/GRC ] Ha, ha. Mostly things are up. The downs are when you learn that Congress doesn't think building a next generation Concord is important enough to give money to it like they just did. The HSR project is being cut way back. [Ms.Metcalf/Yokayoschool-Ms.Metcalf/Yokayo] How long do jet engines last? [ KellyMcEntire/GRC ] Jet engines last many years. Engines can be repaired just like a car engine to make them last longer. Parts that wear out are replace. [Dean-Mr.Richard/homeschool] What kind of plane/plane engine has benifited man the most? [ KellyMcEntire/GRC ] I think type of plane that has benefited man the most is the passenger jet. It given all of us the ability to travel virtually anywhere on earth whenever we want to. [Ms.Metcalf/Yokayoschool-Ms.Metcalf/Yokayo] Are there any plans to make any new designs in space vehicles? [ KellyMcEntire/GRC ] Oh yes. The space shuttle is way too expensive to use. We need much cheaper way to get to space, to get satellites up in space, etc. We are working on several new rocketships to do this. [Ms.Metcalf/Yokayoschool-Ms.Metcalf/Yokayo] What advice could you give to young people about a career in science? [ KellyMcEntire/GRC ] Don't let science or math scare you. It is fun. Science describes everything around you. We take for granted the many things that surround us, but all many made objects are there because someone was interested in science. Things that occur naturally can be described with science. When an apple fell on the head of Sir Issac Newton, he figured out a way using math to describe its fall. This was Calculus. Calculus is not something scary, but something cool, because it describes nature. [Ms.Metcalf/Yokayoschool-Ms.Metcalf/Yokayo] Yokayo school has a science club for upper elementary students. We are going to space camp, and to the Jason Project this year. The students are very excited about space and NASA. Thank you for your time answering our questions. Have a great day. [ KellyMcEntire/GRC ] You're welcome. [ Oran/NASAChatHost - 74 - 10:59:53 ] At this time, we would like to thank everyone for joining us for today's Aerospace Team Online chat with Kelly McEntire from NASA Lewis Research Center. A very special thanks to Kelly McEntire for sharing his time, experiences and expertise with us online today.