Assessment ScoreCard – 31 Day

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

20/04/2023 19:39:48

UK Postcode

WELWYN-GARDEN-VILLAGE , HERTFORDSHIRE , AL6 9BH

Baseline geo-coordinates

51.8199 , -0.243803

Survey type

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

Assessment band

INTERMITTENT

Assessment actual value

5.87

Assessment description

Sound equates to a "C" road or an active country lane i.e. irregular traffic volumes. Location is on a flight route as opposed to a flight corridor. Some of the flights will be below 7000 feet and could occur at evenings and weekends.

Band range

Lower: 4.0 --> Upper: 7.0

Volumes, Height bands, and Intensity.

For Assessment / Daily Avg. / Hourly Avg.

Count of ALL flights

1,205 / 38.9 / 2.3 ✔

Flights above 26k feet.

252 / 8.1 / 0.5 ✔

Flights between 16k and 26k feet

289 / 9.3 / 0.5 ✔

Flights between 13k and 15k feet

64 / 2.1 / 0.1 ✔

Flights between 7k and 12k feet

333 / 10.7 / 0.6 ✔

Flights between 6k and 7k feet

73 / 2.4 / 0.1 ✔

Flights between 5k and 6k feet

88 / 2.8 / 0.2 ✔

Flights between 4k and 5k feet

82 / 2.6 / 0.2 ✔

Flights between 3k and 4k feet

11 / 0.4 / 0.0 ✔

Flights below 3k feet

13 / 0.4 / 0.0 ✔

4 or more flights per hour

71 / 2.3 ✔

9 or more flights per hour

1 / 0.0 ✔

Departures between 1.5k and 15k feet

502 / 16.2 / 1.0 ❌ (413)

Time and Sleep Analysis

For Assessment / Daily Avg. / Hourly Avg.

0 AM

9 / 0.3

1 AM

6 / 0.2

2 AM

11 / 0.4

3 AM

13 / 0.4

4 AM

3 / 0.1

5 AM

4 / 0.1

6 AM

59 / 1.9

7 AM

72 / 2.3

8 AM to 9 PM

958 / 30.9 / 2.2

10 PM

42 / 1.4

11 PM

21 / 0.7

Other Noise Disturbance, Vibration and Emissions factors

Time in seconds an aircraft existed in the airspace bubble

16 ✔

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

53 ❌ (43)

Minimum avg. distance in miles

0.49

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

15.0 / 8.0 / 0.8 ✔

Flight holding stack identified?

No

Altitude for all flights

17,102 ✔

Altitude of departures between 1.5k and 15k feet

8,486 ✔

Altitude of flights below 20k feet

8,746 ✔

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

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

5.00

Tuesday @ 15:00 - 4 time(s) in 4 weeks. Approx:3 flight events.

9.17

Sunday @ 14:00 - 3 time(s) in 4 weeks. Approx:5 flight events.

7.33

Sunday @ 19:00 - 3 time(s) in 4 weeks. Approx:4 flight events.

6.33

Sunday @ 15:00 - 3 time(s) in 4 weeks. Approx:4 flight events.

5.33

Sunday @ 16:00 - 3 time(s) in 4 weeks. Approx:3 flight events.

4.83

Monday @ 18:00 - 3 time(s) in 4 weeks. Approx:3 flight events.

4.50

Wednesday @ 19:00 - 3 time(s) in 4 weeks. Approx:2 flight events.

4.17

Monday @ 15:00 - 3 time(s) in 4 weeks. Approx:3 flight events.

3.67

Monday @ 13:00 - 3 time(s) in 4 weeks. Approx:3 flight events.