A lifting body is a fixed-wing aircraft or spacecraft configuration in which the body itself produces lift. In contrast to a flying wing, which is a wing with minimal or no conventional fuselage, a lifting body can be thought of as a fuselage with little or no conventional wing. Whereas a flying wing seeks to maximize cruise efficiency at subsonic speeds by eliminating non-lifting surfaces, lifting bodies generally minimize the drag and structure of a wing for subsonic, supersonic and hypersonic flight, or spacecraft re-entry. All of these flight regimes pose challenges for proper flight safety.
Lifting bodies were a major area of research in the 1960s and 70s as a means to build a small and lightweight manned spacecraft. The US built a number of lifting body rocket planes to test the concept, as well as several rocket-launched re-entry vehicles that were tested over the Pacific. Interest waned as the US Air Force lost interest in the manned mission, and major development ended during the Space Shuttle design process when it became clear that the highly shaped fuselages made it difficult to fit fuel tankage.
Advanced spaceplane concepts in the 1990s and 2000s did use lifting-body designs. Examples include the HL-20 Personnel Launch System (1990) and the Prometheus spaceplane (2010). The Dream Chaser lifting-body spaceplane, an extension of HL-20 technology, was under development as of 2012 as one of three vehicles to potentially carry US crew to and from the International Space Station. In 2015 the ESA Intermediate eXperimental Vehicle performed the first ever successful reentry of a lifting body spacecraft.
I had a piece of box section steel tubing, 400mm long, 5 x 10cm section, 3mm thick. It has a foot welded to the bottom which stabilises it at the floor (this is in red). It is a weight lifting bench.
I needed to shorten the length, so I cut it in two and overlapped a join, then fixed it with 3...
Homework Statement
I am trying to understand the logic behind the water pump that requires a user to take into consideration the volume of water at sub-intervals of depth of a tank. There are two types of problems, one where the volume changes at different depths, and one where it doesn't. In...
Homework Statement
A power screw with a pitch of 1 mm is directly coupled to a stepper motor rotating at 60 rpm. If
the efficiency of the power screw is 35%, what is the stepper motor torque required to raise a
4450 N (1000 lb) load?
Homework Equations
P=τ*ω
τ=F*r
The Attempt at...
Thank you in advance for your help!
Consider a lifter performing a bench press. The weight of the bar is 225 lbs. Assume the duration of the entire movement from the lowest point to the highest is 1 sec., and that the bar will move a total of 2 ft. from the lifter's sternum to the height of his...
I am reading Dummit and Foote, Chapter 10, Section 10.5, Exact Sequences - Projective, Injective and Flat Modules.
I need help with a minor step of D&F, Chapter 10, Theorem 28 on liftings of homomorphisms.
In the proof of the first part of the theorem (see image below) D&F make the following...
I am reading Dummit and Foote, Chapter 10, Section 10.5, Exact Sequences - Projective, Injective and Flat Modules.
I need help with a minor step of D&F, Chapter 10, Theorem 28 on liftings of homomorphisms.
In the proof of the first part of the theorem (see image below) D&F make the following...
Dummit and Foote open their section (part of section 10.5) on projective modules as follows:D&F then deal with the issue of obtaining a homomorphism from D to M given a homomorphism from D to L and then move to the more problematic issue of obtaining a homomorphism from D to M given a...
I need some help understanding work.
If a man lifts a box up to a shelf and a woman lifts the same box up to the same shelf in half of the time, who is doing more work?
I understand that they're moving it the same distance but isn't the woman using more force because she is getting it to...
hey guys, new here. need some kind of help
im required to design a gearbox which will be used to life an object of 2kg. details of the motor used are as follows:
http://www.jaycar.com.au/productView.asp?ID=YM2712
have been trying to calc the number of gears needed, number of teeth on each...
I am not clear about the difference between Pradtl's lifting line theory and Weissinger's. The latter is applied to swept-back wing but does that involve chord-wise circulation distribution?
This seems simple but I am having trouble with this. I have 70' self supporting tower that I want to be able to raise and lower with a winch. The tower is hinged at the base.
I want to use rectangular steel tubing 7' high with a pulley at the top.
See PDF attachment. I need to know the force...
Dear Advisor,
I tried to read books and searched all around before posting new topic here... I'm carying out testing a hoisting winch at load 400 kN through a system as in picture.
My problem is that due to fiber rope i only can measure exactly wire tension by a load cell installed through...
Homework Statement
This crane lifts a 125 kg heavey motor. What is the member forces of BF and BD?
Use 10 m/s^2 as accleration of gravity.
https://dl.dropboxusercontent.com/u/11241083/problemtruss.png
Homework Equations
F=ma
Sum Fx=0
Sum Fy=0
Sum M=0
The Attempt at a...
Hello,
I have been performing an experiment in which I am observing the lifting capacity of DC electromagnets while changing variables including current, number of turns, and length of the core. It is a fairly basic experiment as all the theoretical values can be obtained using the formula...
Homework Statement
My apologies if the error is an obvious one and many thanks in advance for any help given:
I am trying to create a Matlab code that simulates Lifting Line Theory in order to provide an estimate of the lift and drag of a 3D wing. My hope is to later use this as part of...
I'm trying something similar, it's a mechanism to lift/tilt a cylinder, in order to drop whatever is inside the cylinder into another box. (the substance cannot be pumped)
The cylinder is about 250kg heavy, and I'd have to lift it around 1,5m, then tilt it.
I'm afraid I can't lift it with...
Need engineering help -- lifting 1000 lbs 16 feet
Ladies & Gents,
I am trying to engineer a lifting device. I can build the frame and all that but getting the motor and gearbox sized right is my problem. I am not a math wizz. Some algebra in middle school many many years ago .
The load...
I am trying to make a floating sentry bot ; though, my plan was to use Helium or with a mixture of Ammonia. I want to find the minimum amount of gas in a balloon require to reach the max height the object should float. I know the buoyancy force is Density * Volmin * g : where the maximum...
When a person pushes up a weight like in this picture http://www.freefitnessguru.com/Anatomy/images/military%20press%205%20combined.jpg the weight is exerted on the wrist. So when the weight is stationary, the downwards force acting on the wrist is equal to the weight of the object. However...
1. The hydraulic lift at a repair shop is filled with oil. The car rests on a 25-cm-diameter piston. To lift the car, compressed air is pushed down on the 6-cm-diameter piston.
a) What air-pressure force will support a 1300kg car level with the compressed air piston?
b) How much must the...
Homework Statement
See attachment
Homework Equations
The Attempt at a Solution
I think I just need a kickstart figuring out what the forces in the vertical direction of F and G are. I am guessing F and G are exerting a force in the direction of their normal, but I have no idea...
I have one interesting question :-)
How many balloons would be needed for lifting house? Which variables need to know? How can I calculate it for a particular case? (my house :-D)
Thanks very much and sorry for my bad English.
So I decided to go back to a gym membership and get back in shape. About 3 years ago when I was still in grad school I benched about 40 lb dumbells and squatted with 55 lb dumbells. I also rowed with 50 lb dumbells, and military pressed 35-40 lb dumbells. I went to the gym today for the first...
Homework Statement
Find the work done in winding up a 150 ft cable that weighs 4.00 lb/ft. Assume that the weight includes the gravitational force. In order words exclude the gravitational force g in your calculation.
Homework Equations
W = ∫ pgA(y)D from a ft to b
a = area
P =...
So basically, at my work at a science center, we have this exhibit where you lift yourself using different pulleys. I noticed that the pulleys were labeled wrong. They should have been, 1/2, 1/3, and 1/5 but were labeled, 1/3, 1/4, and 1/6. I brought this up with management and received an email...
Homework Statement
The end of a chain of length L and mass per unit length ρ, which is piled up on a horizontal platform is lifted vertically with a constant velocity u by a variable force F. Find F as a function of height x of the end above platform.
A)ρ(gx+2u^2)
B)ρ(gx+u^2)
C)ρ(2gx+ρu^2)...
Homework Statement
A large tower crane is used to move heavy objects
in a construction site. The crane uses a counter
weight with a mass of mw = 1w.0 Mg (mega
grams), and the top beam of the crane also has a
mass of mc = 1x00.0 kg which is evenly distributed
along the beam. The length of...
Hello to the Forum.
I just started doing some very light weight lifting and decided to do a rough calculation of how many calories I might be burning during each of my workouts, however the figure I arrive at seems too high by comparison with the numbers one regularly see bandied about. What...
Hello,
I've been wondering for a while now how hot air balloonists figured out how big their balloons needed to be to lift themselves, the basket,the balloon itself, ect. Is there an equation that would tell me how much lifting force I could get out of x amount of air at x temperature, what...
Hi I'm having a very hard time trying to picture an argument in Feynmans physics volume one ). I can't picture this example he is talking about, so I wrote it down from the book and really hope someone can help me answer the question in the bottom.
From the book (everything needed to know...
Homework Statement
A 7-kg box is being lifted by means of a light rope that is threaded through a single, light, frictionless pulley that is attached to the ceiling. If the box is lifted, at constant acceleration, from rest on the floor to a height of 1.5 m above the floor in 0.42 s, what...
Hi guys,
I am studying aerospace engineering doing my final year. I am doing my final year project which is called "Development of Aircraft Wing Design Tool using MATLAB". It is basically to create a basic tool which will help a designer to design wings. I am totally confused on how to go...
Hello All,
I am brand new to this forum and have found information on here quite helpful in the past before I decided to join the forum, so hopefully some of you can help me with my current project.
Currently I am trying to design and fabricate a lifting hook for rolled steel cans. The...
On 2 October, 5 days from now, Derek Wise will give an online international seminar talk which will be a followup to his June 2012 paper with Stefen Gielen---as I recall a lot of us found that paper very interesting and it topped the second quarter MIP poll.
So I want to review that paper, the...
I am trying to build a helicopter. please help me.
I want to know how much RPM and size of blade needed to lift 90KG of weight.
I am planning not to use tail rotators, but I have a solution for this.
Hi I like to play basketball and am curious as to how much force is required to jump a certain height I have tried to calculate it but I get stuck at energy and am not sure how to find the force as it is difficult to measure without equipment and being very accurate and precise (unless there is...
Homework Statement
A party balloon(of mass 0.0025kg when empty) is filled with helium to a volume of 0.0045m3. it is tied to a small stone of mass 0.015kg by a light string of length 1.5m to prevent it from flying away. a child holds the balloon at ground level and then releases it...
Dear fellows
I have three questions related to the topic “Lifting an object against gravity”.
If we lift an object of mass 5kg we need to apply a little more force than its weight to lift it and suppose we apply 50 N force (gravity is exerting 49 N forces on it) for just a second that...
Dear all,
I am following Warren F. Phillips' book "Mechanics of Flight" (2nd edition) and am trying to code the numerical lifting line method outlined by him starting on page 96 of Chapter 1.
I will write the code in Matlab, but what is preventing me from doing so is a few variables within...
Homework Statement
A prism has a mass of m = 80 g, and you wish to lift it, touching
the upper two faces only. If the coecient of friction between the prism’s surface and
your skin is = 0:4, what is the minimum force that must be applied to each face?
Homework Equations
F=μR...
If work is displacement times force, lifting a weight up and bringing it down to the same spot would have zero displacement, and thus zero work is done.
However, isn't work a path function? In thermo we learned that heat and work were path functions while quantities such as internal energy and...
Homework Statement
A bucket of water is raised up out of
a well with a device of the rope, and
pulleys as shown in figure. The bucket is hanging from the
the lower hook and the upper hook is
attached to a fixed cross bar of the well. If
the mass of the bucket and the water together
is m, and...
Homework Statement
A large (15,000-kg) military helicopter lifts a 6000-kg truck straight up out of a danger zone with an acceleration of 4 m/s2. Calculate the tension in the lifting cable.
Homework Equations
F = ma
W = mg
The Attempt at a Solution
I believe T = 8.3 * 104N...
Homework Statement
You are pulling on a rope attached to the outer radius of a pulley with a moment of inertia I=676 kgm2 as shown. The tension in the rope that you are pulling is 477.9 N. A pack of mass 30.8 kg is attached to the pulley's inner radius as shown. If the inner radius of the...
Gentlemen please.
I am trying to find out how much a motor can lift through a gear reduction to a drum connected a block and tackle assembly.
The motor can develop 16K N-M of torque, through a gear reduction of 7.51, turning a drum having a diameter of 1 meter, using 0.0508 meter rope. there...
Homework Statement
The crates( one create 500 kg) are placed on a hydraulic lifting beam:
1. State the order of lever used here
2. Calculate the effort required to lift the load
3. Calculate mechanical advantage for this system
4. Calculate the velocity ratio for this system. If the...
Homework Statement
Alright, so my calc class isn't getting easier and we started doing 'work' problems, and I'm just not getting it. Here's the question: A 10ft long weighs 25l and hangs from a ceiling. Find the work done in lifting the lower end of the chain to the ceiling so that its level...
I was thinking about the work-energy theorem today and how it states that:
Wnet = ΔEkinetic
If this is true, then when a ball is moved upward a distance of d, the net work done is equal to zero because there is no change in kinetic energy.
Because: Work = Force x Displacement
for...