Official 66 Task 1
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An airship is a type of aircraft that flies using a very large balloon filled with a lighter-than-air gas. Airships were an important means of air transportation before the 1940s but are lite used today, having been largely replaced by airplanes and helicopters. However, some aeronautical engineers believe that airships could become popular again because they offer a number of advantages over airplanes and helicopters.

One advantage of airships is that for vertical lift (the force that keeps the ship airborne), they use a balloon that floats rather than an engine. Airplanes and helicopters use engines for both vertical lift and horizontal movement, but airships use engines solely for horizontal movement. So, airships use less fuel than a typical aircraft- -thus making their fuel costs more economical.

Another advantage of airships is that they can be used in hard-to-reach locations. Unlike airplanes, airships do not require a long runway for takeoff and landing because of their ability to lift off and land vertically. The only other aircraft capable of ascending into the sky by going straight up and descending straight down to the ground is the helicopter, which can carry only a small amount of weight. Airships, meanwhile, are able to carry very heavy loads. As a result, airships could do jobs that neither airplanes nor helicopters can do, such as carrying heavy logs from forests to distribution centers.

Finally, airships could even be used to replace satellites. Currently, satellites are launched into Earth's orbit carrying all kinds of equipment important in telecommunications or in surveying large areas of Earth's surface for military purposes. Since airships can also rise high above the surface and stay there without refueling for a significant amount of time, they could provide services similar to those provided by satellites, and at a considerably cheaper cost.

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NARRATOR: Now listen to part of a lecture on the topic you just read about.
MALE PROFESSOR: Despite what was stated in the reading, there are several reasons why airships are not likely to be widely used in the future.
Yes, airships use less fuel, but don't forget that air ships also require special lighter than air gases that give them lift.
The two most efficient lifting gases are hydrogen and helium, and each has its own problems.
Hydrogen catches fire easily, and this has led to many tragic airship accidents in the past.
Helium is safer, but it is difficult to obtain expensive and it doesn't provide as much lifting power as hydrogen.
So, finding a truly economical solution for the lifting gas as a solution that balances safety and cost is not an easy matter.
Second, using airships for picking up loads off the ground has its challenges.
Imagine for a second an airship picking up tree logs in a forest.
It has to slowly come down, pick the logs up, and then safely rise again.
Throughout this process, the airship has to be kept very steady, so as to pick up the load safely and not crash.
But airships are large and light like balloons, it's difficult to keep them steady, especially under windy conditions.
A sudden gust of wind can easily blow the airship against the surrounding forest trees and seriously damage it.
Finally, airships are not quite ready to replace satellites yet.
You see the types of airships currently in use can only rise to heights of about 14 kilometers above the surface.
The problem is that at that height, there are very strong winds.
Airships have to spend a lot of their fuel to resist those winds and stay in one place, which they need to do to carry out telecommunications or surveying functions.
So, the airships, working at that height, quickly use up the fuel and have to descend and refuel.
So right now, they cannot provide the kind of continuous uninterrupted service satellites can.
Question

Summarize the points made in the lecture, being sure to explain how they present solutions to the specific problems mentioned in the reading passage.