Nah. I don't remember, but I think the engineers got that off pretty quick after takeoff.
We always used a 'quiet EPR' second stage climb so we really weren't climbing all that fast anyway!
Typed in the B-727
- Thread starter Bandit_Driver
- Start date
Nah. I don't remember, but I think the engineers got that off pretty quick after takeoff.
We always used a 'quiet EPR' second stage climb so we really weren't climbing all that fast anyway!
jwp_145
GhostRider in the Sky
Hey Doug what is the A-mode and B-mode on the 727, and where are said controls located? Or is it an operating envelope?
jwp_145
GhostRider in the Sky
No I don't think so.. the guys a couple pages ago were talking about cruising at 320 IAS and mentioned that the cargo birds were always flown in B-mode and that to fly at 400 IAS when the plane was in A-mode would produce the greatest cockpit noise... I think that is the terminology they were using.
Orange Anchor
New Member
The A and B modes were limiting operating speeds. You routinely operated in the A mode which was a switch on the airspeed indicators which reset Vmo/Mmo limits. In the A mode or with ZFW below 136,000lbs or takeoff gross at less than 172,000lbs, you could go up to around 400kts indicated and 0.90M. If either of those limits were exceeded, you had to fly the B mode which limited you to 350kts and 0.88M
http://www.boeing-727.com/index.htm
OMG, what would kids do these days with round dials and an ODM?
What's that circle thing in the square box with the numbers? My instructor never taught me about that....
jwp_145
GhostRider in the Sky
OMG, what would kids do these days with round dials and an ODM?
Uh, what is an ODM? hahha
THank you Orange Anchor for the information. I love learning about the 72!
I remember my mentor told me that the Caution light he feared the most was the AftBodyOvht or something like that. Said it meant 13th stage bleed air was pouring into the tail structure.
Orange Anchor
New Member
It was serious. I will rummage around tomorrow and find my manual but yes, it was a bleed leak with very hot air where you did not want it.
Bandit_Driver
Gold Member
Thankfully we don't have that here. I have heard horror stories about quiet EPR settings.
OMG, what would kids do these days with round dials and an ODM?
Crash and burn...
A Lower Aft body heat ovheat warning is an absolute nightmare to deal with as the procedure is lengthy and bleed leak in that area can be disasterous.
The lower aft body area includes the keel beam and the area above the aft cargo compartment. It contain heat sensing elements. A heat rise in any of these areas will light illuminate a warning light on the Flight Engineer's panel.
There is no fire bottle provided to combat an overheat condition. The only corrective action available is to reduce or turn off bleed air.
The procedure is a few pages long and calls for the crew to systematically eliminates vairous bleed sources and ducting as teh overheat source. The checklist is worked in sequences and requires pauses in specific areas to wait for the affect area to cool if isolated the correct bleed or duct.
The problem is if you are wrong the area still has very hot bleed air pouring into and if the keel beem fails it is game over.
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jwp_145
GhostRider in the Sky
The APU was in the mid-ship belly?
Bandit_Driver
Gold Member
The APU was an after thought by Boeing on the 727. A lot the jets of this era require air start carts. However, the airlines wanted to get away from that so the only place Boeing could quickly stick one is between the main wheels in the gear wells.
The air is exhausted thru the top of the right wing. The APU air intake is in the left wheel well along with the flow multiplier. The flow multiplier allows the -200 series aircraft to run two A/C packs off the APU.
The APU can only be used on the ground and must be shutdown prior to takeoff and cannot be started in the air. If the FE forgets to kill it prior to take off it will usually shut down due to lack of air when the gear doors close and you may get a wheel well fire warning or an APU fire warning.
There are also two highspeed pack cooling fans (one on each side of the aircraft) that are used to cool the packs when the aircraft is on the ground or the flaps are not up. These fans alone are louder than most RJ's APU's... lol
Look for the spikes as you crank the packs. Because if those high-draw pack fans don't crank, OOOOOOOOO'WEEEEEEE!
Smokey the Bear says "Only YOU can prevent pack smoke!"
I smoked at least three packs in a year because I tried to crank the cabin down too low and wasn't actively watching the temps on the ground.
Smokey the Bear says "Only YOU can prevent pack smoke!"
I smoked at least three packs in a year because I tried to crank the cabin down too low and wasn't actively watching the temps on the ground.