A WGS-84 coordinates certificate for NOC is a signed survey document giving the latitude and longitude of every plot corner (to 0.1 second) and the site elevation in metres AMSL. AAI’s NOCAS portal needs it to accept a height clearance application. Surveying India prepares it in AAI’s format through its airport NOC survey India service.
Share your plot location and proposed height. We confirm within one working day whether an NOC applies. Call +91 98718 80058.
What is a WGS-84 coordinates certificate for NOC?
When you build near an airport in India, AAI needs to know exactly where your structure stands and how high the ground is at that spot. This certificate records the first part: the surveyed latitude and longitude of your site corners in the WGS-84 datum, which aviation uses worldwide.
It is normally issued together with the site elevation on one prescribed certificate. We cover the elevation side in our guides on site elevation survey for airport NOC and the AMSL elevation certificate.
Why AAI relies on this certificate
Under the Ministry of Civil Aviation’s height rules (GSR 751(E)), structures near notified aerodromes need an NOC before construction starts. You apply on NOCAS, which calculates the Permissible Top Elevation (PTE) from the coordinates you enter. For the legal background, read GSR 751(E) airport NOC rules.
Accuracy matters because AAI’s NOC letter says it does not authenticate your coordinates or elevation, and that the NOC becomes void if the real data is different. The survey is your responsibility, and this certificate is your proof.
How the numbers are used: Maximum structure height = PTE (AMSL) minus site elevation (AMSL). For example, if the PTE is 135.00 m and your surveyed site elevation is 120.00 m, you can build 15.00 m above ground. A 2 m error in elevation changes your allowed height by 2 m.
Whether you need an NOC at all depends on distance and height. Check the colour coded zoning map AAI for your airport, our guide to VFR IFR airport NOC distance, and building height restriction near airport rules.
What the certificate must contain
- Owner or applicant name and signature
- Site name and address, worded exactly as in your NOCAS application
- WGS-84 latitude and longitude of all prominent corners, in DD°MM’SS.s” format (example: 28°35’12.4″N 77°12’30.7″E)
- Highest site elevation in metres AMSL
- Surveyor’s name, licence number, licence validity, signature and stamp
- Survey date and instrument used, in AAI’s prescribed layout
For the full filing pack, use our AAI NOC required checklist, the list of documents required for airport NOC, and NOCAS application documentation.
Who can issue the certificate?
AAI-format certificates are signed by a licensed surveyor, architect or engineer. The signatory should have taken the readings on site, because AAI can assign a panel of chartered engineers and surveyors to verify the details physically.
Defence cases can differ. Some Indian Air Force station notices name a different certifying authority, so confirm it before commissioning the survey. See defence IAF height clearance NOC.
How we prepare your certificate
- Feasibility check: distance to the airport reference point and your CCZM grid, to confirm an NOC is needed.
- Field survey: corner points and ground elevation recorded with DGPS or RTK-GNSS, and a total station where satellite signal is weak.
- Processing: readings converted to WGS-84 degrees, minutes and seconds, with elevation reduced to AMSL.
- Certificate: data entered in AAI’s format with signature, stamp, licence number and validity.
- Cross-check and filing support: address, coordinates and elevation matched with your NOCAS entries. Follow the steps in our NOCAS portal application process guide.
Mistakes that get NOC applications rejected
- Certificate not in AAI’s prescribed format
- Coordinates or elevation in the application differ from the certificate
- Owner name, signature or highest site elevation missing
- Coordinates less precise than one-tenth of a second
- Surveyor licence number or validity missing
- Site name or address does not match across documents
- Unclear scans or files that will not open
Read the full list of airport NOC rejection reasons, what to do after an objection in AAI NOC objection reply, and how to handle wrong coordinates on a rejected NOC.
Check your certificate before you file
A five-minute check saves weeks. Before uploading to NOCAS, compare the certificate with your application line by line:
- The site name, address and owner name are identical in the application, the certificate and the undertaking.
- Every corner you entered on NOCAS appears on the certificate, with the same degrees, minutes and seconds.
- The elevation on the certificate is the same figure you typed into the form, in metres AMSL.
- The surveyor’s licence number and validity are visible, and the stamp and signature are clear.
- Plot the coordinates on a satellite map. They should land on your plot, not on the neighbouring one or the road.
If any item fails, fix the certificate first. Correcting data after AAI has issued an NOC is far harder than getting it right at filing.
Certificates by structure type
- Buildings and towers: building height clearance AAI NOC
- Transmission lines: tower-wise coordinates for transmission tower AAI NOC
- Telecom masts: mobile tower airport NOC rules
- Solar plants: solar power project AAI NOC and solar panel airport NOC limits
- Wind farms: wind turbine windmill AAI NOC and wind turbine height limit airport
Civil AAI NOC vs defence NOC
A site near a military aerodrome may need a separate defence clearance, sometimes in addition to the AAI NOC. Start with defence NOC India, compare the two in defence NOC vs AAI NOC, and see NOC from local military authority construction. For the regulator’s role, read AAI NOC vs DGCA clearance.
Airport NOC Survey Services by City
Looking for an Airport NOC survey? Select your city below.
- Airport NOC Survey in Delhi NCR
- Airport NOC Survey in Mumbai
- Airport NOC Survey in Bengaluru
- Airport NOC Survey in Pune
- Airport NOC Survey in Ahmedabad
- Airport NOC Survey in Surat
- Airport NOC Survey in Dholera
- Airport NOC Survey in Jaipur
- Airport NOC Survey in Kota
- Airport NOC Survey in Chandigarh
- Airport NOC Survey in Lucknow
- Airport NOC Survey in Varanasi
- Airport NOC Survey in Patna
- Airport NOC Survey in Bhopal
- Airport NOC Survey in Indore
- Airport NOC Survey in Nagpur
- Airport NOC Survey in Raipur
- Airport NOC Survey in Guwahati & More
Frequently asked questions
What is a WGS-84 coordinates certificate for NOC?
It is a certificate signed by a licensed professional that records the surveyed WGS-84 latitude and longitude of your site corners and the site elevation in metres AMSL. AAI uses it to calculate the permissible top elevation. See what is AAI NOC for the basics.
Is the certificate mandatory?
Yes. NOCAS guidelines make surveyed WGS-84 coordinates and site elevation mandatory, and the application cannot be submitted without them.
What accuracy does AAI expect?
Coordinates are entered to one-tenth of a second, which is roughly 3 metres on the ground, and elevation is given in metres AMSL. Check the current certificate format on NOCAS before the survey.
Can I use Google Maps or phone GPS coordinates?
No. NOCAS asks for surveyed coordinates from a qualified professional. AAI plots your coordinates on a satellite map, so a mismatch with your real plot can lead to cancellation.
How many points do I need?
NOCAS guidelines ask for all prominent corners of the plot, site or structure. Larger or irregular sites need more points.
How long does it take?
Our survey takes 2 to 5 working days, plus 2 to 3 days for the certificate. AAI’s own scrutiny is separate, see AAI NOC approval time.
What if the data is wrong after the NOC is issued?
AAI’s NOC says the NOC is null and void if the actual data is different from what you submitted. Read what happens with wrong coordinates on an NOC.
Is the same certificate accepted for a defence or IAF NOC?
Not always. A civil AAI NOC and a defence NOC are separate applications with their own documents, and some stations name a different certifying authority. Check the station notice first.
How much does the certificate cost?
Cost depends on plot size, number of corner points, distance from our team, site access, and whether a defence NOC is also needed. We give a fixed quote after a free feasibility check, with no obligation.
How long is an AAI NOC valid?
NOC letters for buildings show an 8-year validity, and AAI’s terms allow up to 12 years for chimneys, masts and similar structures.