Height Clearance Approval from the Airport Authority of India (AAI) is a mandatory regulatory requirement for any structure proposed near an airport or airstrip in India. Whether you are planning a residential building, commercial complex, mobile tower, crane operation, or infrastructure project, obtaining AAI height clearance ensures that the structure does not obstruct aircraft movement or compromise aviation safety. This guide explains the complete step-by-step process, eligibility, documents required, and important guidelines for smooth approval.
What Is Height Clearance from AAI?
Height clearance is an official permission issued by the Airport Authority of India or the Civil Aviation Authority to confirm that a proposed structure complies with the obstacle limitation surfaces (OLS) defined around airports. These surfaces are imaginary planes that limit the height of objects in and around aerodromes to ensure safe take-off and landing of aircraft.
AAI evaluates the geographic location, distance from the airport, and proposed height of the structure before granting approval.
Why Is AAI Height Clearance Mandatory?
AAI height clearance is compulsory because:
- It ensures aviation safety and prevents air navigation hazards
- It is legally required under Aircraft Act, 1934 and Aircraft Rules, 1937
- Local municipal authorities cannot issue building permits without AAI approval
- Non-compliance can result in demolition notices, penalties, or legal action
Any structure exceeding the permissible height within a notified airport zone must obtain clearance.
Structures That Require Height Clearance Approval
Height clearance from AAI is required for:
- Residential and commercial buildings
- High-rise apartments
- Mobile and telecom towers
- Chimneys, hoardings, and signboards
- Windmills and solar plants
- Cranes (temporary or permanent)
- Infrastructure projects such as bridges and flyovers
Even temporary structures may require approval if they exceed height limits.
Step-by-Step Process to Get Height Clearance from AAI
Step 1: Identify Airport Proximity
Determine whether your project site falls within the influence zone of an airport. Most airports have restricted zones extending up to 20 km or more. This information can be verified through local planning authorities or the AAI NOCAS portal.
Step 2: Register on the NOCAS Portal
AAI has made the process online through the No Objection Certificate Application System (NOCAS). Applicants must:
- Create an account on the NOCAS portal
- Select the nearest airport
- Enter project location coordinates (latitude and longitude)
Accurate coordinates are critical to avoid rejection.
Step 3: Submit Project Details
Upload complete project information including:
- Type of structure
- Proposed height above ground level
- Plot size and land-use details
- Building layout plan and elevation drawings
For buildings, the maximum height including parapet, lift room, and water tank must be clearly mentioned.
Step 4: Upload Required Documents
Key documents required include:
- Site location plan
- Survey map with coordinates
- Architectural drawings
- Ownership documents
- Local authority letter (if applicable)
Incomplete or incorrect documents can delay approval.
Step 5: Pay the Applicable Fees
AAI charges fees based on structure type and height. Payment is made online through the portal. Fee structure may vary for residential, commercial, or telecom projects.
Step 6: Technical Evaluation by AAI
AAI conducts a technical assessment based on:
- Obstacle Limitation Surfaces (OLS)
- Airport runway orientation
- Aircraft approach and departure paths
- Existing obstacles in the area
If the structure complies with safety norms, clearance is granted.
Step 7: Issuance of Height Clearance Certificate
Once approved, the Height Clearance Certificate (NOC) is issued online. This document must be submitted to local municipal authorities before construction begins.
Timeframe for Approval
Typically, height clearance approval takes:
- 15–30 working days for standard cases
- Longer if clarification or revisions are required
Delays usually occur due to incorrect coordinates or incomplete documentation.
Common Reasons for Rejection
Applications may be rejected due to:
- Incorrect latitude and longitude
- Proposed height exceeding permissible limits
- Inaccurate building drawings
- Proximity to critical flight paths
- Non-compliance with OLS norms
Revisions can be submitted if allowed by AAI.
Important Guidelines to Follow
- Always verify permissible height before finalizing building design
- Include all rooftop structures in total height
- Do not start construction before receiving approval
- Height clearance is location-specific and non-transferable
- Any design modification requires fresh approval
Conclusion
Height Clearance Approval from AAI is a crucial step for any construction project near an airport in India. Understanding the process and following the correct steps can save time, money, and legal complications. By applying through the NOCAS portal, submitting accurate details, and adhering to aviation safety norms, applicants can obtain clearance smoothly. Always consult professionals or planning authorities to ensure full compliance and avoid delays.
