MmM Flight Test — will it fly?

Step 1 Pick your material

The seven Mind My Material families. Each one opens to the real materials inside it — 45 altogether — and each of those carries its own real numbers: how hot it can get, how stiff it is, how heavy, how strong, how well it takes a knock, what it costs, and how it handles sun, water, salt and wear.

Pick the family your quiz gave you, then pick a material inside it. The amber tag is that material’s call sign in the iSight Air Flight Academy story. The line under each family is the mission the whole family does best, on average.

Step 2 Pick a mission

A way of living, written down as a pattern of loads. There is no best material — only the right kind of mission for each one.

Six of these eight are real missions in the reference workbook. The last two, Test bed and Depot, are places in that workbook rather than missions — somewhere you get measured, and somewhere you get repaired. They are drawn with a dashed edge, their numbers are this page’s own, and they never count as a material’s best mission.

What each life actually does to you

Think of a paper clip. Bend it once and nothing happens. Bend it back and forth fifty times and it snaps in your fingers, cold. That is what a life does to a material: not one big blow, but a great many bends.

So each life is written down as a list of bends — how many small ones, how many big ones, per thousand hours. The number on the left is the size of the bend: 0.10 is a gentle one, 0.50 is halfway to the hardest pull the aircraft is built for, and 1.10 is going past it. The bar shows how often that size happens. Blue bends are easy, amber ones are hard, rust ones are the rare brutal ones.

Bars use a squeezed scale, so a bar twice as long means many times more bends, not twice as many. A fighter and an aerobat spend real time in the amber and rust. A transport and a sailplane almost never get there.

Where the counts come from. Each mission is one real aircraft, named on its card. The limit, the landings, the sun and the wet under each chart are estimates for that aircraft. The counts of bends are not: they are the typical shape for that kind of aircraft, not measured on the one named.

The dark panel draws those same bends as a line, in order: small ones on the left, the rare big ones on the right. The rust dashed line at the top is UTS — the pull that would break the material outright. The blue dashed line is the hardest pull the aircraft is built for (UTS ÷ 1.5), and the grey one is level flight. Even the biggest bend stays under the rust line: no aircraft is meant to get there. Pick a mission above to highlight it.

Or fly a mission mix — real life is rarely one mission

A season is usually a blend: 60% Transport, 25% Fighter, 15% Depot. Allocate yours — the sliders normalize to 100% — and fly the blended spectrum. In Hindsight Daily you can declare the same mix and check it against the spectrum you actually flew.

Set at least one slider above zero.

Step 3 Fly the service life

Pick a material and a mission, and watch the stand-in fly until it wears out.

Stand-in —flying—

How used up it is After 9,000 hours in the air — thirty years, at 300 hours a year: —

0 · brand newhalf worn1 · worn out

When to give it its first proper check — this page’s own estimate; the workbook does not cover checks Past worn out — further than this model can speak for

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Match, out of 100

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How long it lasts

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hours in the air

What wears it out

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the one thing that uses it up

Check it every

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half the time a crack takes to grow

Recommended repair technique

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The working — every number, and where it came from ▾

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Size of bend	Pull (g)	Swing	Steady part	Scaled up to	Bends it would take	Bends it gets	Share used
Total used by bending, per 1,000 hours							—

The seven things that use it up

Bending is only one of them. Here is everything that wears this material out on this life, per 1,000 hours in the air, and how much of the total each one accounts for. Nearly every verdict comes down to a single line.

The grid Every family, every mission

Its best mission — of the six missions, the one this material handles best. Its second best — the runner-up. It manages this one too. Not its mission — one of the other four. Not a failing; just the wrong fit.

The whole picture at once. Each number is the match, 0 to 100, for the material named on that row. Change the material above and its row follows.

Every material comes first at something. Nothing here was decided in advance — each one earned its place by the same arithmetic.

Its best of the six missions Its second best — it manages this one too Not its mission — the wrong kind of wear for it A place, not a mission — this page’s own numbers

“Not its mission” does not mean weak. It means the mission is leaning on qualities that material does not happen to have. Move it to the mission it was made for and the same material reads completely differently. This grid measures fit, never worth.

The small line under each family name is the mission the whole family does best on average, then its runner-up: Metals the sailplane (then the trainer) · Ceramics the transport (then the sailplane) · Polymers the trainer (then the aerobat) · Elastomers the trainer (then the aerobat) · Foams the trainer (then the rescue) · Natural the trainer (then the sailplane) · Composites the aerobat (then the fighter).

The method How the number is worked out

Eight steps, in ordinary words. Every one of them is visible in The working above, so you can watch each step move as you change things.

First, make it a fair contest. Every material gets a wing built to suit it, sized so that the hardest pull puts the same share of that material’s own strength on the one spot that cracks first. Otherwise steel would win every round simply for being steel. What a stronger material actually buys you is not a gentler ride — it is a lighter aeroplane. Some missions care about that a great deal (a sailplane lives or dies by weight) and some hardly at all (a trainer just has to be cheap and tough).
Write the mission down as a list of bends. Not one dramatic event — a great many ordinary ones. So many gentle bends per thousand hours, so many hard ones, a handful of brutal ones. That list is the only thing that separates one mission from another.
Work out what each bend costs. Three things decide it. A bend hurts more if the material is already being pulled steadily while it happens — so the bend gets scaled up by how much steady load it is riding on. Real things break at holes, corners and sharp steps rather than in the smooth middle — so it gets scaled up again. And then the material’s own wear-out line says how many bends of that size it could take before breaking. Do that for each size of bend, work out what fraction of its life each one used, and add them all up.
Add the six other things that wear it out. Bending is not the only way to use something up. A steady load it never puts down makes it slowly sag — and the closer a material is to its own melting point, the faster. Sunlight makes some materials brittle, unless they get a protective coat. Rain and salt eat at others. Every landing is a knock, and what survives a knock is not raw toughness but how much energy the material can swallow before it cracks. Fast shaking builds heat inside rubber and foam. And a stretch held too long never fully springs back — which is why rubber perishes in a clamp and not on a bouncing wheel.
That gives you the hours. Add all seven up into one wear-per-thousand-hours figure, and the hours it lasts is 1,000 divided by that. Hours in the air is the headline number, because it is the workbook’s own unit. The years beside it are this page’s own translation, at 300 hours a year — about an hour a day, six days a week.
First half of the score: how long it lasts. Take those hours, give credit for flying lighter, and place the result against the best material on that same mission. Scored on a squeezed scale, so doubling the hours counts the same whether it is 200 to 400 or 20,000 to 40,000 — which is how service life honestly reads.
Second half: whether it suits the job at all. Thirteen real qualities — strength for its weight, stiffness for its weight, how well it takes a knock, raw strength, heat, sun, water, wear, cost, weight, how forgiving it is, how it handles impact, how far it bends before it stays bent — each scored against all 45 materials and weighted by what this particular mission actually asks for. This half catches what lasting a long time cannot: performance, cost, and forgiveness.
The match is the two, averaged. Half how long it lasts, half how well it suits the job. Highest of the six missions is what that material is built for; next is its second best. A family’s answer is the average of its members. That is the whole of it.

Three things this cannot see It only judges aeroplanes. A crash pad and a crewman in the door do real work that has no column here.

It rewards lasting longer than anything needs to. Something that would survive 400,000 hours is not four times better than something that survives 100,000 — nobody flies either that long — but the score still counts it, which nudges metals and ceramics toward the gentle missions.

A family average hides its members. Six materials in a family can average to one answer while two of them belong somewhere else entirely.

Each mission is one aircraft Nate chose — the F-5E fighter, the DG-1001 (Aero) sailplane, the C-47 Skytrain transport, the Zivko Edge 540 aerobat, the T-6A trainer and the Westland Sea King HAR3 rescue helicopter. Their limits, sortie lengths, landings and exposure to sun and wet are his estimates for those aircraft; the counts of bends in each band are class-typical shapes, not measured on them.

None of the starting numbers are measurements from a real aircraft. Change one and everything downstream moves — which is exactly why they are written down where you can see them.

If a word here was new

Stand-in: An aeroplane that exists only as numbers. You never fly it; you just work out what would happen to it.
A bend: One load and release. A gust, a turn, a landing. The paper clip you bend back and forth until it snaps.
Limit load: The hardest pull an aircraft is built to take in normal service. On the charts, band 1.00 is exactly that pull; 1.10 is going past it.
g: How heavy everything feels. At 1 g you weigh what you weigh; at 4 g, four times that. The fighter here (the F-5E) is built for 7.33 g, the transport (the C-47 Skytrain) for 2.5.
Squeezed scale: A scale where each step means many times more, not a few more — used because these numbers span from ten to ten million.
Wear-out line: The material’s own answer to “how many bends of this size before it breaks?” Gentle bends, an enormous number. Hard bends, very few.
The one spot that cracks first: Nothing breaks everywhere at once. There is always one hole, corner or joint that goes first, and that is the only place worth watching.
Test bed · Depot: Two places rather than two missions. The Test bed is where you find out what you are made of. The Depot is where you get repaired and get your coat back.

Hindsight Daily · fly it as a life

The same missions, in the Daily app

The Mission tab in Hindsight Daily uses the same eight names as this page — Fighter, Sailplane, Transport, Aerobatic, Trainer and Rescue, plus the two places, Test bed (try a life change out) and Depot (deliberate ground time). Pick the one you’re flying, name it in your own words, and one tap a day tracks whether the days build it.

Tell the Daily your material family and it puts a ✦ on that family’s best and second-best missions — the same pair this page prints under each family name. A mirror, not a verdict: a family average can hide its members, so your own material’s row here is the closer read.

Fly it — Hindsight Daily The framework — a life in damage units

Will it fly? Depends what’s loading it.

This test flies your material through a mission. The free body diagram reads the forces on you right now — lift, weight, thrust, drag, wind, and the gust — and tells you whether today’s balance is a climb, a cruise, or a descent nobody declared.

Open the free body diagram — i5.2.2

What’s your specific spectra?

iSight Laboratories has built and proven out a tracking program for human wellness — Hindsight 80/20. To begin capturing your life’s flight data today, join the fleet-tracking iSIP program.

Open the fatigue sheet