Assessment ScoreCard – 31 Day

Aircraft Traffic Assessment: 31 Day Scorecard



The symbol indicates the measure is better than the average when compared with other assessed
UK postcodes. The ❌ represents the opposite. Assessed averages are shown in brackets.

See: for a full explanation about the Assessment scorecard.

Assessment Scorecard headlines

All Assessments are based on an ambient background noise of 40 decibels i.e. a quiet residential area. If your property is located near to a busy road i.e. 70-75 decibels, the noise impact from aircraft will be significantly reduced, whilst the road remains busy.

Note: Airborne aircraft noise is typically in the range of 45dB - 65dB for heights below 26,000 feet and for a duration of 30-50 seconds. Whereas the average car, bus or HGV the duration is only a few seconds.

Date of survey

21/02/2024 09:50:05

UK Postcode

NORTHCHURCH , HERTFORDSHIRE , HP4 1LB

Baseline geo-coordinates

51.7856 , -0.59636

Survey type

31 days from the 1st date shown in the Evidence table below .

Assessment band

REGULAR

Assessment actual value

10.16

Assessment description

Sound equates to a "B" road or busy "C" road i.e. regular traffic that will be noticeable at peak times which includes evenings and weekends. Location is on a secondary flight corridor or flight route or in a flight holding stack area. At times there will be multiple flight occurrences within the same hour, typically 4. Some of the flights will be below 7000 feet.

Band range

Lower: 7.0 --> Upper: 12.0

Volumes, Height bands, and Intensity.

For Assessment / Daily Avg. / Hourly Avg.

Count of ALL flights

3,103 / 100.1 / 5.9

Flights above 26k feet.

355 / 11.5 / 0.7

Flights between 16k and 26k feet

726 / 23.4 / 1.4 (324)

Flights between 13k and 15k feet

152 / 4.9 / 0.3

Flights between 7k and 12k feet

1,057 / 34.1 / 2.0 (490)

Flights between 6k and 7k feet

356 / 11.5 / 0.7 (166)

Flights between 5k and 6k feet

283 / 9.1 / 0.5 (263)

Flights between 4k and 5k feet

145 / 4.7 / 0.3

Flights between 3k and 4k feet

3 / 0.1 / 0.0

Flights below 3k feet

26 / 0.8 / 0.0

4 or more flights per hour

368 / 11.9 (217)

9 or more flights per hour

66 / 2.1

Departures between 1.5k and 15k feet

1,604 / 51.7 / 3.0 (413)

Time and Sleep Analysis

For Assessment / Daily Avg. / Hourly Avg.

0 AM

10 / 0.3

1 AM

14 / 0.5

2 AM

10 / 0.3

3 AM

9 / 0.3

4 AM

16 / 0.5

5 AM

11 / 0.4

6 AM

207 / 6.7

7 AM

258 / 8.3

8 AM to 9 PM

2,455 / 79.2 / 5.7

10 PM

65 / 2.1

11 PM

39 / 1.3

Other Noise Disturbance, Vibration and Emissions factors

Time in seconds an aircraft existed in the airspace bubble

18

Percentage of overflying occuring Out-Of-Hours and at Weekends

43

Minimum avg. distance in miles

0.42

Number of possible disruptions by; day / out-of-hours / hour

75.0 / 32.0 / 3.9

Flight holding stack identified?

No

Altitude for all flights

13,822 (16,276)

Altitude of departures between 1.5k and 15k feet

8,085

Altitude of flights below 20k feet

9,740

Busiest times of day
(Distruption: 0 - low, 25+ high)

Day of week, time, frequency and number of flight events.

15.40

Wednesday @ 7:00 - 4 time(s) in 4 weeks. Approx:9 flight events.

11.60

Thursday @ 18:00 - 4 time(s) in 4 weeks. Approx:8 flight events.

11.40

Wednesday @ 12:00 - 4 time(s) in 4 weeks. Approx:7 flight events.

11.30

Thursday @ 7:00 - 4 time(s) in 4 weeks. Approx:7 flight events.

11.20

Wednesday @ 14:00 - 4 time(s) in 4 weeks. Approx:7 flight events.

10.30

Thursday @ 12:00 - 4 time(s) in 4 weeks. Approx:6 flight events.

10.10

Friday @ 7:00 - 4 time(s) in 4 weeks. Approx:6 flight events.

9.50

Wednesday @ 6:00 - 4 time(s) in 4 weeks. Approx:6 flight events.

9.00

Friday @ 6:00 - 4 time(s) in 4 weeks. Approx:6 flight events.

Our scorecard is designed to provide a greater understanding how the assessment was reached for your selected UK post code. To enable you to validate our assessment we also provide up to 10 occurrences when we believe the disruption will be at its highest.

For those that would like to perform their own analysis we can also provide the low level flight data that includes the length of time a plane existed inside your select airspace bubble.



Evidence by associated Airport – indicative only: NORTHCHURCH

UK Airport Count of Flights Percentage of Total
MINOR UK AIRPORT?274488.5
TRANSATLANTIC FLIGHT?35811.5