science

URMV-3 IS-4

URMV-3 IS-4 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 URMV-3 IS-4 rather than just read about it. In short: The IS-4 was a high performance glider designed by Iosif Şilimon and built in Romania in the late 1950s at the URMV-3 (Rom: Uzinele de Reparatii Material Volant-3 - Glider repair and manufacture factory) factory at Braşov. Design and development The IS-4 high-performance glider followed the layout of the earlier IS-3d, constructed largely of wood with plywood and fabric skinning.

Key takeaways

URMV-3 IS-4 belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect URMV-3 IS-4 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of URMV-3 IS-4 from memory before moving on to harder problems.

Reference excerpt

The IS-4 was a high performance glider designed by Iosif Şilimon and built in Romania in the late 1950s at the URMV-3 (Rom: Uzinele de Reparatii Material Volant-3 - Glider repair and manufacture factory) factory at Braşov.

Design and development The IS-4 high-performance glider followed the layout of the earlier IS-3d, constructed largely of wood with plywood and fabric skinning. The high-set cantilever wings with moderate dihedral (2º 30') were built with a single main spar with a plywood covered leading edge torsion box. The ovoid section fuselage was of monocoque construction with plywood skin with a streamlined full-length cockpit canopy forward of the wings. The undercarriage consisted of a balloon main-wheel with nose and tail skids. Flying controls were largely conventional with plywood skinned fixed portions and fabric covered wooden built up movable surfaces. Pitch trim was achieved by a trim tab on the elevators and adverse yaw was alleviated through the use of differential ailerons. Very little is known of the IS-4s development or operational history.

Specifications (IS-4) Data from The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs du Monde Volume IIGeneral characteristics Crew: 1 Length: 7.1 m (23 ft 4 in) Wingspan: 15 m (49 ft 3 in) Height: 0.9 m (2 ft 11 in) at cockpit Wing area: 14 m2 (150 sq ft) Aspect ratio: 16 Airfoil: Root:Göttingen 549, Mid Göttingen 549, Tip Göttingen 693 Empty weight: 210 kg (463 lb) Gross weight: 320 kg (705 lb) Performance

Stall speed: 60 km/h (37 mph, 32 kn) Never exceed speed: 200 km/h (120 mph, 110 kn) *Rough air speed max: 150 km/h (93 mph; 81 kn) Aerotow speed: 120 km/h (75 mph; 65 kn) Winch launch speed: 90 km/h (56 mph; 49 kn) Terminal velocity: with full air-brakes at max all-up weight 185 km/h (115 mph; 100 kn) g limits: +5 -3 at 250 km/h (135.0 kn) Maximum glide ratio: 30 at 80 km/h (50 mph; 43 kn) Rate of sink: 0.64 m/s (126 ft/min) at 41.6 mph; 36.2 kn (67 km/h) Wing loading: 22.9 kg/m2 (4.7 lb/sq ft)

Worked examples

Example 1 — a first encounter with URMV-3 IS-4

Start with the simplest possible case. Write down what URMV-3 IS-4 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 URMV-3 IS-4 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 URMV-3 IS-4 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 URMV-3 IS-4

In research: URMV-3 IS-4 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 URMV-3 IS-4 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: URMV-3 IS-4 is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1950s Romanian sailplanes, Glider aircraft, so understanding it makes those chapters shorter.
In everyday life: Look for URMV-3 IS-4 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.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “URMV-3 IS-4” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study URMV-3 IS-4 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what URMV-3 IS-4 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 URMV-3 IS-4 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is URMV-3 IS-4 in simple terms?

Why does URMV-3 IS-4 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 URMV-3 IS-4?

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 URMV-3 IS-4.