Free mechanical comprehension practice: app, examples and answers (2026)
Free mechanical comprehension practice in 2026: Brain Preflight gives you 5 free iPhone sessions immediately and every day, with diagram questions, five answer options and explanations in English, French and German.
Start your 5 free daily sessionsBy Brain Preflight, the app developer · Updated 29 October 2026
What a mechanical-comprehension question asks you to do
A technical diagram is a compact set of relationships. Before calculating, identify what is connected, what stays fixed and what the question actually asks. A gear-direction problem needs no speed calculation. A lever-distance problem needs moments, not a guessed proportional drawing. A pressure question needs the force and area in compatible units. This habit is useful in SPHAIR preparation and the DLR-related SWISS routine. The examples below are original practice, not official test questions.
Gears and belts: follow each connection
Two meshing gears reverse direction. An open belt keeps the direction; a crossed belt reverses it. Follow a chain one connection at a time. For speed, multiply the driving speed by driving teeth and divide by driven teeth. An intermediate idler does not change the ratio between the first and last gear’s tooth counts.
A 15-tooth gear turns at 120 rpm and drives a 45-tooth gear. What is the output speed?
120 × 15 ÷ 45 = 40 rpm. The larger driven gear turns more slowly. If the gears mesh directly, its direction is opposite. Direction and speed are separate questions.
Levers: force × distance from the pivot
For a balanced ideal lever, moments on the two sides match. Use the perpendicular distance to the force’s line of action. In the simple diagrams used here, the force acts downwards and the arm is horizontal, so the marked arm length is the relevant distance. Do not use the total beam length when the question gives distance from the pivot.
A 90 N load sits 2 m from a pivot. What effort balances it at 3 m?
90 × 2 = F × 3, so F = 60 N. A useful check is that the longer arm requires less force.
Pulleys: count supporting rope segments
In an ideal system with one continuous rope, negligible friction and negligible pulley weight, rope tension is equal along the rope. Count the segments supporting the moving load, not every vertical line in the diagram. More supporting segments reduce the effort, but you must pull more rope for the same lift.
Four rope segments support a 240 N load. What effort holds it, and how much rope lifts it 1 m?
The effort is 240 ÷ 4 = 60 N. Each supporting segment shortens by 1 m, so 4 m of rope must be pulled. These answers assume the ideal conditions stated.
Pressure and hydraulics: compare areas
Pressure equals force divided by area. If an ideal connected hydraulic system applies the same pressure to both pistons, the output force scales with piston area. Use area, not diameter: if a question gives diameters, area grows with the square of the diameter. Also check the units before substituting values.
A 50 N input force acts on a 2 cm² piston. The other piston has an area of 10 cm². What is its force?
The area ratio is 10 ÷ 2 = 5, so the output is 50 × 5 = 250 N. Both areas use cm², so their ratio is valid.
Springs, scales and how to review an error
Within the linear range, spring extension is proportional to force. Two identical springs in series each carry the load and their extensions add. In parallel, identical springs share the load. For scale drawings, a scale of 1:20 means each drawing length is multiplied by 20 to obtain the real length. Keep length, force and extension distinct in your working.
In the app, choose Mechanical comprehension and answer the five-option questions. You can go back, review the response summary and submit when ready. Read the explanations afterwards. Classify an error as connection, formula, unit or arithmetic; then solve a fresh item using the corrected method. For a trainee application use the Edelweiss guide or SPHAIR-versus-DLR comparison. The Swiss overview links the wider selection routes.
Practise now in Brain Preflight
Download Brain Preflight free on iPhone. You get 5 free exercise sessions immediately and 5 new sessions every day, with any exercise available in your chosen language. No purchase or subscription is required for that daily allowance. Installed exercises work offline. Mechanical comprehension is available in English, French and German. Premium is optional and adds unlimited sessions, ad-free practice, the app’s own timed series or mock-exam routines, and detailed diagnostics. The free plan may show ads. Choose a programme in the app, review your exercise feedback and adjust tomorrow’s practice to the mistakes that actually recur.
Start your 5 free daily sessionsFrequently asked questions
Can I practise mechanical comprehension for free?
Yes. Brain Preflight includes Mechanical comprehension in English, French and German. Use the five free daily sessions on this or any available exercise.
What topics are in the mechanical exercise?
Generated questions cover gears and belts, levers, pulleys, hydraulics, springs and drawing scales. A question bank adds tools and mechanical facts.
Are these official SPHAIR or DLR questions?
No. These examples and the app’s questions are original skills practice. Use official familiarisation resources for the actual selection instructions.
Official sources and familiarisation
Independent app developed by Brain Preflight. Not affiliated with SPHAIR, DLR, SWISS, Edelweiss, Skyguide, EFA or EUROCONTROL. Practice levels are not official selection scores.