science

X-15 Flight 90

X-15 Flight 90 is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand X-15 Flight 90 rather than just read about it. In short: Flight 90 of the North American X-15 was a research flight conducted by NASA and the US Air Force on July 19, 1963. It was the first of two X-15 missions that passed the 100-km high Kármán line, the FAI definition of space, along with Flight 91 the next month.

Key takeaways

X-15 Flight 90 belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect X-15 Flight 90 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of X-15 Flight 90 from memory before moving on to harder problems.

Reference excerpt

Flight 90 of the North American X-15 was a research flight conducted by NASA and the US Air Force on July 19, 1963. It was the first of two X-15 missions that passed the 100-km high Kármán line, the FAI definition of space, along with Flight 91 the next month. The X-15 was flown by Joseph A. Walker, who flew both X-15 spaceflights over the Kármán line.

Crew

Mission parameters Mass: 15,195 kg fueled; 6,577 kg burnout; 6,260 kg landed Maximum Altitude: 106.01 km., 347,800 feet Range: 534 km Burn Time: 84.6 seconds Mach: 5.50 Launch Vehicle: NB-52B Bomber #008

Mission highlights Maximum Speed - 5,971 km/h. Maximum Altitude - 106,010 m. 80 cm diameter balloon towed on 30 m line to measure air density. First X-15 flight over 100 km (a height known as the Kármán line). This made Walker the first US civilian in space. This was also the first spaceflight of a spaceplane in aviation history. First flight launched over Smith Dry Lake, NV. Experiments: Towed balloon, horizon scanner, photometer, infrared and ultraviolet. Balloon instrumentation failed. The mission was flown by X-15 #3, serial 56–6672 on its 21st flight. Launched by: NB-52B #008, Pilots Fulton & Bement. Takeoff: 17:19. UTC Landing: 19:04 UTC. Chase pilots: Crews, Dana, Rogers, Daniel and Wood. The X-15 engine burned about 85 seconds. Near the end of the burn, acceleration built up to about 4g (39 m/s²). Weightlessness lasted for 3 to 5 minutes. Re-entry heating warmed the exterior of the X-15 to 650 °C in places. During pull up after re-entry, the acceleration built up to 5g (49 m/s²) for 20 seconds. The entire flight lasted about 12 minutes from launch to landing.

Notes

References Goodwin, Robert (2000). X-15: the NASA mission reports, incorporating files from the USAF. Burlington, Ontario: Apogee Books. ISBN 1-896522-65-3. Jenkins, Dennis R. (2000), Hypersonics Before the Shuttle: A Concise History of the X-15 Research Airplane, NASA Technical Reports, NASA, hdl:2060/20000068530, Document ID: 20000068530 Price, A. B. (1968), Thermal protection system X-15A-2 Design Report, NASA Technical Reports, NASA, hdl:2060/19680016245, Document ID: 19680016245 Stillwell, W. H. (1965), X-15 research results with a selected bibliography, NASA Technical Reports, NASA, hdl:2060/19650010561, Document ID: 19650010561 Watts, Joe D. (1968), Flight experience with shock impingement and interference heating on the X-15-2 research airplane, NASA Technical Reports, NASA, hdl:2060/19920075739, Document ID: 19920075739

Illustrations

Worked examples

Example 1 — a first encounter with X-15 Flight 90

Start with the simplest possible case. Write down what X-15 Flight 90 claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to X-15 Flight 90 before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about X-15 Flight 90 ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of X-15 Flight 90

In research: X-15 Flight 90 appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses X-15 Flight 90 in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: X-15 Flight 90 is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1963 in spaceflight, X-15 flights, so understanding it makes those chapters shorter.
In everyday life: Look for X-15 Flight 90 outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study X-15 Flight 90 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what X-15 Flight 90 means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain X-15 Flight 90 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is X-15 Flight 90 in simple terms?

Why does X-15 Flight 90 matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study X-15 Flight 90?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on X-15 Flight 90.