Friday, December 18, 2015

My favorite aircraft

    Here's a topic that you'd probably expect. "What is my favorite aircraft?" I honestly don't have a single favorite aircraft. I really like airplanes so I can't pick one. For small prop planes; I like the Cessna Caravan and the 172/182's. I like the caravan because it's pretty much a van with wings. You can configure it for a vacation with your friends, carry cargo, or give it a limo style interior. The 182 was the first plane I ever flew so it have memories attached to it and same with the 172; both used by Civil Air Patrol. 







     For Cargo aircraft, Ill go with the C-130 because of its versatility. I wouldn't be able to guess all the different roles it can take on. Fire fighting, gun ship, vehicle transport, reconnaissance, refueling, and even pick people up off the ground.
The right one isn't a real C-130 but I'm sure they can make the plane do that if they really wanted to. For fighter jets, it's the F-22. Bombers would be B-1. I like the B-1 because of its speed and maneuverability compared to the B-2 and B-52. 
B-1

F-22

Thursday, December 17, 2015

Rockets

     Rockets are not the same as airplanes but they do own a big part of the aerospace community and that's why I'm going to talk about them. Rockets can be thought of as slick chemical reactors that travel high and fast. Not all rockets go to space, these are usually model rockets used for sports and recreation.
     There are a few main parts to a rocket; nose cone, fuselage, stabilizers, and engine. For rockets going to space they will have a guidance system and many sensors.
 
Amateur rockets will use the nose to store a parachute or not use it at all while space rockets put their payload in them. Just below will house a guidance system so the rocket knows where its going and makes the necessary corrections to stay on course. The fuselage will hold the main fuel tanks for the rocket's propulsion systems. The fins on the bottom of the rocket are stabilizers; they act similarly to the stabilizers on the tail of a plane, keeping the craft from spinning out on any of the 3 axis of flight. They also can move to change direction in flight like the control surfaces on a plane. The engine is the last part which is key to get off the ground.
     Rocket engines are powerful pieces of machinery. Solid rockets ignite a chemical and it burns up. Liquid rocket engines will take fuel from the tanks and mix it thoroughly before combustion. The mix is sent to a combustion chamber then ignited. The exhaust gas goes through the throat at supersonic speed and expands around the cone applying newtons 3rd law. Forces from the expanding gas push on the cone giving it lifting force to get off the ground. 
     Rockets aren't that fuel efficient in general. The reason they're used so much is because rockets generate a lot of thrust; enough to get itself into space.
     There are many types of rockets in means of propulsion devices.

  1.  "The solid motor is used mainly as a booster for launch vehicles. Solid motors are almost never used in space because they are not controllable. The boosters are lit and then they fire until all the propellant has burned. Their main benefits are simplicity, a shelf life which can extend to years as in the case of missiles, and high reliability."
  2. "Liquid motors come in many shapes and sizes: Most of them are controllable (can be throttled up and down), restartable, are often used as control and maneuvering thrusters. Liquid thrusters can be broken into three main types: monopropellant, bipropellant, and cryogenic thrusters. Monopropellants only use one propellant such as hydrazine. Bipropellants use a fuel and an oxidizer such as RP-1 and H2O2. Cryogenic systems use liquefied gases such as LiH and LOX (liquid hydrogen and liquid oxygen). Cryogenic means super-cooled. You would have to super-cool hydrogen and oxygen to make them liquids. With each step from mono-propellant to bi-propellant to cryogenic the thruster complexity goes up but the performance also goes up.
  3. "Cold-gas motors have controllability similar to liquids but are the simpler and lighter. They are basically a high pressure tank with switches which flip between the open and shut state. They function a little like spray paint, with the contents under pressure inside, and when the valve is opened, they stream out."
  4. "Ion engines are vastly different from chemical (solid, liquid) engines in that they are low thrust engines which can run for extended periods of time. The length of use of chemical engines is usually from seconds to days while the length of use of ion engines can be anywhere from days to months."(Northwestern)
     Lately many other forms of propulsion are under research, I'm guessing so they can achieve the president's goal set for Mars. Nuclear thermal powered rockets are another type; similar to chemical rockets but they're much more efficient because of increased exhaust velocity compared to a chemical rocket. NASA also is currently working on this new design that is truly unique, a propulsion system that uses microwaves to generate thrust. Since there's no propellant then this engine would violate the conservation of momentum and it shouldn't work but thrust was recorded. That being said NASA is checking this thing out to try to understand where the thrust is really coming from. This new design can potentially be used to get humans to Mars within the president's goal. Exciting to see what space travel will be like in the next 25 years is were going to Mars in hopefully <3 years.


Northwestern. "Propulsion." What Are the Types of Rocket Propulsion? Northwestern.edu, n.d. Web. 18 Dec. 2015. <http://www.qrg.northwestern.edu/projects/vss/docs/propulsion/2-what-are-the-types-of-rocket-propulsion.html>.

Monday, December 14, 2015

My first blog

     Hola, mi nombre es Roberto y soy un gringo (jajaja). This is my first ever blog; I will mostly be discussing anything aerospace, hence the name of the blog. But for specifics I'll talk about my flying experiences, do comparisons of different aircraft and a little bit of anything else. My dream is to become a pilot. It's pretty funny because I'm afraid of heights, but I guess I'm afraid more of heights when I'm not secured to anything. So pretty much I get scared chilling on a balcony but I can care less at any altitude in an aircraft.
     I have flown a plane 6 times before and the aircraft I flew were a Cessna 182, Cessna 172 and a Piper.
 
Above is a Civil Air Patrol Cessna 182. In Civil Air Patrol, I'm entitled to 5 orientation flight at no charge. I got my 6th from an aviation summer camp from Millionaire Mind Kinds and Young Eagles.

Friday, November 6, 2015

Design

      Besides wanting to be a pilot, flying in the sky, I also have great interest in designing and building aircraft. Pretty much, when an aviator goes to the airline for a job they'll need a bachelor degree to get hired. Not many places offer a degree in flying; even though there are degrees for flying, I choose to get a degree in aerospace engineering to pursue my second passion of aerospace design. I've had ideas of building many different aircraft since I was little, one being a tilt rotor quad-copter plane. I think it's so cool to be able to produce a thought, draw it, explain it, and then do the math and physics to make it come alive.
     Making an aircraft is hard but also not really lol. An airplane needs a cabin (unless its an unmanned aircraft), fuselage, wings, tail, and engine; those are the basic parts, easy right? Now the hard part would be to put all those together in an aerodynamic design, keep it light and strong, safe, run efficiently, and not become overly pricey. A good aviation masterpiece will need a lot of physics and math done in order to make it possible, like the SR-71 Blackbird. It wasn't cheap but it was able to reach nearly the top of the atmosphere and go faster than mach 3. The SR-71 was really expensive so its lifespan wasn't too big but looking at a different aircraft like a Cessna 182 and you come across another great plane. It's not as fast or as strong but it has advantages that the blackbird (SR-71) didn't have. The 182 is light, safe, waayyy more fuel efficient, and they're cheaper to operate.
    The design in aircraft now is different from the first commercial aircraft. They would never thought of using jet engines, now that's almost all you see running planes. About every decade an aircraft will have something new to its design structure.
Boeing 777
   To the left is a Boeing 777. This aircraft features a delta wing, a triangle shaped wing, and the wings are swept back. The reason for swept wings are to help lower drag since these aircraft fly close to the speed of sound, which generate shock waves. This is is because the chord line, line from front to end of the wing, isn't parallel to the direction of  flight so shock waves, which generate huge drag, are delayed to a faster speed. This increases efficiency, lowers noise and vibrations, and allows the plane to preform better.

Boeing 787
   Now to the right is a Boeing 787. This aircraft is much newer to the 777 above. As you can see the wings curve upward as if the plane is suspended by two strings on the ends. The 787 in this picture has its flaps retracted, looks like the pilot is going for a landing by the angle of attack, retracted flaps, and retracted gear. These wings have a great amount of flexibility because of the new type of material utilized to make the wing. The wing is made up of a more lighter, but stronger, material and this new material is more flexible than existing wing materials still used. The curve does lose lift but its not a significant amount but a pro to cover up is that there is less turbulence. Less turbulence since the air vortices produced roll outward on the wing; less vibrations, noise, and drag.
Airbus 320
   Talking about vortices rolling off the wing, we see above an A320. Now on this aircraft we see that the tips of the wing go from parallel to the floor then take off strait up. On the tip of the wings there is a great vortex of air generated that creates a strong opposing force. Engineers discovered that curving the tip of the wings up helps dissipate this vortex with a significant increase in efficiency.
   It may look like all these aircraft that the average passenger will fly in all look the same and that's because its almost true. The aircraft manufactures want to incorporate theses new technologies into their jets for better performance, higher efficiency, and passenger comfort and safety. These planes are familiar today but in three decades.... they're relics, in the history books.



Tuesday, September 22, 2015

Flying experiences

    Flying is truly remarkable. Many people get their experience of flying from being a passenger in a commercial aircraft. For others their experience is doing the actual flying and being a pilot lets you really understand what flying is like.
    As a passenger in a commercial aircraft you don't get to experience too much. Sit back, look out the window and maybe you'll feel a little bit of g forces every once in a while; plus turbulence, lol there will always be turbulence.  Now if you were a private pilot flying your own aircraft you could do so much more that would get you arrested so quick or potentially killed if you were to attempt in a commercial plane. That's why I don't think of commercial flight as a real flying experience, unless you're flying in the mountains of Indonesia or Malaysia.
    Being a private pilot with a sports rating and sport plane you can do many things. Some maneuvers are barrel rolls, inverted flight, loops, stalls and going negative g's. I personally was able to pull negative g's and positive g's but I prefer zero g's. G stands for gravity. Anytime that you're not accelerating you will be at 1 g which is just your normal weight. At zero g's then everything experiencing it will be weightless, anything higher than 1 g will be heavier.
     I have also experienced stalls and preformed a stall a couple times during a flight. I was nervous but also really excited. So after take off my orientation pilot let me take the controls and gave me a heading and altitude to fly, when we got to altitude I gave the pilot back the controls. We were discussing why and how aircraft stall prior to me returning the controls because it's a learning flight. So as we discussed, he lowered the throttle and kept the same angle of attack; our airspeed started to drop. I could see that he had to constantly pull the controls back slowly (pull up), and when he couldn't pull anymore a few seconds later while still losing airspeed the alarm went off, lots of vibrations, and then a sudden nose drop free fall. I felt nervous when I saw the nose of the plane pointed strait down. The pilot waited about 3 seconds so i can fully experience the stall then went full throttle, picked up speed, and then pulled up to level the wings to the horizon.
   Stalls happen when an aircraft has too much angle of attack or to dumb it down, not enough airspeed for the angle the plane is flying at, so the plane drops. Stalls aren't hard to recover from unless you don't have any engine power. They must be avoided at low altitude or the plane could crash because you lose altitude really quick. That's why take offs and landings are crucial times for a plane because that's when the aircraft is at low altitude and low airspeed. Take offs are not as stressful as landings because the airspeed and altitude are increasing but if engine power is lost then things can get worse than just a lost engine.