We a chasing a very elusive noise at the VIP floorboard area. Climb only. Slats clean only. 4000 to 20,000 feet only. Starts out as a hoot, then drives the floor enough to see your legs move.
Only replicates occasionally.
Sirenage was the obvious first suspect. we did a full blast replacement of all seals and sirenage strips.
Now, we seem to have confirmation that the Wing Tank Regulating Valve over pressurize enough to crack the clapper valves at Frame 25. This drives the (empty) forward tank through the over wing vent tube….possibly.
Take off is at 4:20, max O’press is at 5:20, then the clapper valves obviously crack open.
here is the PDF of the flight profile. The camera shutoff at about 6 min in.
N716BH JUNE 22 TEST FLIGHT flight profile
_______________
Previous troubleshooting areas.
AERO DYNAMIC
STRENAGE –
NACA SOCOR
GEAR DOORS
FLAP FAIRIMES.
LANDING LIGHT LENSES.
STRUCTURAL
– EXTERFOR PANEL –
PRESSURE-WATER
HEIR – DOOR SEAL, BUNDS, WINDOW SEALS HYDRAULIC
FUEL PRESS – UNWANTEU VENTING
FAN
DRAIN VALVE BOX
DOOR SEALE
TEMPURATORE
HOT COLD MIX,
DUAL VALVES
CROSS OVER DUCTS.
______
AJ
AP disconnect
Ovation screens
Headset jack
Start fuel
BH
Gear doors
Pressure
Power cycle @ 9:23
Tanks dump @ 10:00
Tank press. @ 10:01
Tanks dump during climb @ 10:17
Fuel 3597
?
Aerodynamic
Speed
AOA
Maneuvering – climb only
Landing light cooling ducts
NACA scoops
Structural
Main entry door seal
Sealant (seals)
Slipper fairing on tail
Antenna loose, sealant
Gear doors
Pressure
Cabin diff
Fuel tank, clapper and pressure valve
Hydraulic, park brake valve
Conditioned air, flapper valves (cycled valves)
Reading light fans
Park brake
Neg press @ aileron
Side drain tubes
Sink drain
BAG ISO
?
After L.E. retracted + 30 seconds (e.g. 4000 ft)
Noise 4000 ft to 10,000 ft
All slat seal
1 test flight 4000 to 10,000
With pressure valve & clapper
Pressure valve plus 1 clapper
3 trips good local
1 VIP trip good
Noise came back, 7500 ft to 20,000 ft.
?——??——————-