STS category - Specific Category scenarios
STS enables more complex operations through declaration - not an individual authorisation.
What is the STS category?
STS (Standard Scenarios) are EASA-approved operation scenarios in the Specific Category. The operator submits a declaration of use to the competent authority, not an individual SORA authorisation.
It is a simplified path for commercial operations when a standard scenario matches your risk profile.
STS-01 and STS-02
STS-01 - VLOS operations with C5-class aircraft. STS-02 - BVLOS with C6, airspace observers and additional mitigations.
- STS-01 → C5
- STS-02 → C6
- Both require declaration
- FTS mandatory
EASA categories explained
EU drone operations are classified by risk. Open Category covers A1, A2 and A3 subcategories - each with different distance and environment limits.
When standard Open Category rules do not allow your planned operation, you need Specific Category - typically STS scenarios with a risk assessment.
A1 and A3
A1 allows certain operations closer to people with compliant aircraft (e.g. C0, C1). A3 covers flights further away (≥50 m) from uninvolved persons, often in industrial areas.
A2
A2 lets you fly closer to people than A1/A3 in Open Category - but requires an additional theory exam and usually a C2-class aircraft.
STS (Specific Category)
STS-01, STS-02 and other scenarios apply to commercial operations needing deeper risk management and procedural knowledge.
EU drone exam formats (NAA)
Across the EU, remote pilot qualifications are assessed by your National Aviation Authority. Each category has a different test format - prepare for the exact exam you plan to sit.
A1/A3: 40 questions in 40 minutes (renewal: 20/20). A2: 30/30 min. STS: 60/60 min. All require ≥75% to pass.
- A1/A3: 40 q, 40 min, 75% threshold
- A2: 30 q, 30 min, 75% threshold
- STS: 60 q, 60 min, 75% threshold
- 5-year renewal - shorter formats per NAA rules
STS preparation plan - 6-8 weeks
Structured STS preparation typically takes 6-8 weeks with 15-30 minutes daily. Week 1-2: review 8 STS syllabus areas and topic tests. Weeks 3-4: strengthen weak areas. Final weeks: full timed simulations.
Never book the NAA exam until you consistently score ≥80% in simulations. A failed attempt costs extra fees and wasted time.
Weeks 1-2
Review all topics; use learning mode with explanations.
Weeks 3-4
Topic tests; focus on weakest areas from your stats.
Week 5+
Full simulations, mistake review, repeat registration and rules questions.
How A2STS helps with STS preparation
A2STS is a specialised preparation platform with a 545+-question bank, topic learning, explanations and NAA-format simulations. Free A1/A3 lets you start risk-free; premium unlocks full A2 and STS exam simulations.
The most effective model: regular topic tests (15-30 min daily), wrong-answer review (SRS) and full simulations in the final weeks. Aim for a stable ≥80% before booking your NAA exam.
- Learning mode with explanations after each answer
- Quick tests - time pressure and focus
- Full exam simulation - exact question count and timer
- Topic statistics - see weak areas
- Mistake review - SRS for long-term retention
Common STS exam mistakes
These errors cause most STS failures. Address them in practice before you pay for the official test.
- Treating STS like a longer A2 exam - procedural topics are separate
- Skipping human factors and air law (11 questions each)
- Ignoring multi-statement questions - evaluate each statement
- Underestimating the 60-minute endurance requirement
How to book your NAA drone exam
First, register as a drone operator in your national UAS portal and obtain an operator registration number. Without it you cannot fly registered aircraft legally or book a qualification exam.
When ready, select the qualification level (A1/A3, A2 or STS), pay the NAA fee and receive your exam slot. Format (online or in-person) depends on your authority.
- Register operator and aircraft in the national UAS system
- Choose qualification level (A1/A3 → A2 → STS as needed)
- Prepare with timed simulations (A2STS)
- Book the official exam and follow NAA rules on the day
EASA and your NAA - official sources
A2STS content aligns with Regulation (EU) 2019/947 (Part-UAS), EASA AMC/GM and common NAA practice. Official certificates and exams are organised by your National Aviation Authority - A2STS is preparation only.
Always verify current requirements on your NAA website before booking - national procedures may be updated.
- EASA Easy Access Rules for UAS
- National UAS portal - registration and exams
- GEO zones and NOTAM - before every flight
- 5-year renewal - shorter exam formats
Why prepare with A2STS?
Official-format exam simulations
A1/A3, A2 and STS practice tests match official question counts, time limits and the 75% pass threshold - you prepare for the real exam, not a random quiz.
545++ question bank
Comprehensive questions with explanations, topics and spaced repetition (SRS). See weak areas and track progress in real time.
Free A1/A3 foundation
Sign up in about a minute. Full A1/A3 theory and tests are free with no expiry. Premium unlocks A2/STS full simulations only.
Prepare anywhere
Study on phone, tablet or desktop. You still take the official exam at your National Aviation Authority (NAA) - A2STS helps you prepare more efficiently.
Prepare for your NAA exam today
Start free with the A1/A3 foundation. Premium A2 and STS simulations - one-time payment, no subscription.
Trust and transparency
- Not an NAA partner - clear role
- A2STS is a preparation platform. Official certificates and exams are organised by your National Aviation Authority. We are not affiliated with any NAA.
- EASA regulations kept current
- Content follows EU Part-UAS requirements and common NAA practice. Transparent information on categories, validity and renewal.
- 9 in 10 candidates pass
- Structured preparation with simulations and topic drills delivers stable results. Start free and benchmark your level before booking the official test.
Frequently asked questions
- Is STS Open Category?
- No - STS scenarios are in the Specific Category.
- How many questions in the STS exam?
- 60 questions in 60 minutes.
- Do I need A2 first?
- Not always mandatory - check your NAA; some include extra A2 questions in STS.
- What aircraft for STS-01?
- C5-class with FTS, Remote ID and declared mitigations.
Pilot reviews
“The timed simulator mirrors the official 30-question, 30-minute session. I passed A2 on the first attempt after two weeks of topic drills - far more reliable than scattered PDFs.”
Marcus W. - A2 passed
“Question wording and pacing felt like the real exam. Wrong-answer explanations fixed my airspace gaps in days, not weeks - I walked in knowing exactly where I stood.”
Sofia R. - First attempt
“The learning hub kept STS prep alongside A2 without juggling tools. Progress tracking and one-time access - no subscription churn - made it easy to justify to my team.”
James P. - A2 + STS
Related pages
Register and start learning
Sign-up takes about a minute. You still take the official exam at your NAA - A2STS helps you prepare more efficiently.