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

29/05/2023 17:23:09

UK Postcode

LETCHWORTH-SOUTH-WEST-MAY2019 , HERTFORDSHIRE , SG6 3ND

Baseline geo-coordinates

51.9661 , -0.231118

Survey type

31 days prior to: 29-May-2019 @00:26:46

Assessment band

INTERMITTENT

Assessment actual value

6.54

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

1,769 / 57.1 / 3.4 ✔

Flights above 26k feet.

334 / 10.8 / 0.6 ✔

Flights between 16k and 26k feet

162 / 5.2 / 0.3 ✔

Flights between 13k and 15k feet

94 / 3.0 / 0.2 ✔

Flights between 7k and 12k feet

832 / 26.8 / 1.6 ❌ (553)

Flights between 6k and 7k feet

25 / 0.8 / 0.0 ✔

Flights between 5k and 6k feet

100 / 3.2 / 0.2 ✔

Flights between 4k and 5k feet

189 / 6.1 / 0.4 ✔

Flights between 3k and 4k feet

30 / 1.0 / 0.1 ✔

Flights below 3k feet

3 / 0.1 / 0.0 ✔

4 or more flights per hour

145 / 4.7 ✔

9 or more flights per hour

5 / 0.2 ✔

Departures between 1.5k and 15k feet

754 / 24.3 / 1.4 ❌ (409)

Time and Sleep Analysis

For Assessment / Daily Avg. / Hourly Avg.

Between Midnight and 1am

19 / 0.6

Between 1am and 2am

24 / 0.8

Between 2am and 3am

17 / 0.5

Between 3am and 4am

25 / 0.8

Between 4am and 5am

14 / 0.5

Between 5am and 6am

10 / 0.3

Between 6am and 7am

39 / 1.3

Between 7am and 8am

127 / 4.1

Between 8am and 9pm

1,359 / 43.8 / 3.1

Between 10pm and 11pm

71 / 2.3

Between 11pm and Midnight

58 / 1.9

Other Noise Disturbance, Vibration and Emissions factors

Avg time in seconds an aircraft remained in the airspace bubble

17 ✔

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

42 ✔

Minimum avg. distance in miles

0.45

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

34.0 / 14.0 / 1.8 ✔

Flight holding stack identified?

No

Altitude for all flights

14,886 ❌ (17,496)

Altitude of departures between 1.5k and 15k feet

10,075 ✔

Altitude of flights below 20k feet

9,127 ✔

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

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

7.50

Sundays between 19:00 and 20:00 - 4 time(s) in 4 weeks. Approx:5 flight events.

6.00

Tuesdays between 12:00 and 13:00 - 4 time(s) in 4 weeks. Approx:4 flight events.

3.90

Tuesdays between 10:00 and 11:00 - 4 time(s) in 4 weeks. Approx:3 flight events.

9.75

Wednesdays between 7:00 and 8:00- 4 time(s) in 4 weeks. Approx:6 flight events.

7.63

Tuesdays between 7:00 and 8:00- 4 time(s) in 4 weeks. Approx:5 flight events.

6.88

Sundays between 18:00 and 19:00 - 4 time(s) in 4 weeks. Approx:5 flight events.

6.75

Sundays between 13:00 and 14:00 - 4 time(s) in 4 weeks. Approx:4 flight events.

6.63

Mondays between 13:00 and 14:00 - 4 time(s) in 4 weeks. Approx:4 flight events.