Forward slipping a swept wing, transport category jet

[MikeD]

I want to say something snarky about the A-10, and Mike, and about how Mike's a hack, but I don't want him to forward slip a Mk. 84 into my house

But for the purposes of the discussion at hand. I know that slips are possible, but not very practical in any normal circumstance in a swept wing transport category jet.

I will throw in one last thing since we're talking wing sweep. I don't know if it was the F-117s shape, it's permanent 67 degree wing sweep, or a combo of both; but it did not like being slipped in any way, or on any day. It sould start a bucking like a bronco and thats as far as I've ever seen or taken it.

 

[Hacker15e]

I will throw in one last thing since we're talking wing sweep. I don't know if it was the F-117s shape, it's permanent 67 degree wing sweep, or a combo of both; but it did not like being slipped in any way, or on any day. It sould start a bucking like a bronco and thats as far as I've ever seen or taken it.

There was nothing normal about that plane aerodynamically. It's not surprising that it heavily resisted trying to be flown like one!

 

[beasly]

For people, like me, who don't know what part 25 is.

[h=3]Part 25[/h] This Part contains airworthiness standards for airplanes in the transport category.
Transport category airplanes are either:

• Jets with 10 or more seats or a maximum takeoff weight (MTOW) greater than 12,500 pounds (5,670 kg); or
• Propeller-driven airplanes with greater than 19 seats or a MTOW greater than 19,000 pounds (8,618 kg).

The Boeing 737 and later types, and Airbus A300 series, are well-known airplane types that were certificated to FAR Part 25.
Most of the Federal Aviation Regulations, including Part 25, commenced on February 1, 1965. Prior to that date, airworthiness standards for airplanes in the transport category were promulgated in Part 4b of the US Civil Air Regulations. The Boeing 707 and 727 are two well-known airplane types that were certificated to CAR Part 4b.

 

[beasly]

Not sure where you got this impression, but it is incorrect. Boeing's will structurally fail if you do the doublet also. Boeing ran the scenarios after that accident, but did not advertise the results!

What is a doublet?

Edit: Never mind, somebody posted a pdf extract that probably described it. the word 'Doublet' sounds like a light tapping on the rudder pedals, but the pdf said full deflections each way--I am guessing that is it.

 

[Cptnchia]

For people, like me, who don't know what part 25 is.

What is a doublet?

Hmm.... Maybe less time drinking and more time studying?

As the great Dean Wormer said, "Fat, drunk and stupid is no way to go through life son."

 

[Autothrust Blue]

What is a doublet?

Edit: Never mind, somebody posted a pdf extract that probably described it. the word 'Doublet' sounds like a light tapping on the rudder pedals, but the pdf said full deflections each way--I am guessing that is it.

Correct. Full, continuous stop to stop rudder movement. See: American 587.

 

[derg]

What does a compressor stall feel like and how is it detected?

I am assuming thrust is lost as there is limited air going through the engine, but can it damage the engine or cause it ti flame out? Also, just curious, but what does it feel like? Does the plane feel like the engines quit and go nose down suddenly?

Oh, you'll know.

Especially in the 727, it's like someone firing a shotgun from the aft cabin or at least a big ***FOPP!!!***

 

[SpiceWeasel]

Oh, you'll know.

Especially in the 727, it's like someone firing a shotgun from the aft cabin or at least a big ***FOPP!!!***

Not a Fap?

 

[Autothrust Blue]

Oh, you'll know.

Especially in the 727, it's like someone firing a shotgun from the aft cabin or at least a big ***FOPP!!!***

All Hail The Steamjet! Protect Essential!

It's quite noticeable in back.

 

[seagull]

All Hail The Steamjet! Protect Essential!

It's quite noticeable in back.

My favorite was "essential power, max power, gear up, flaps up, dump, standby rudder on!"

 

[Autothrust Blue]

My favorite was "essential power, max power, gear up, flaps up, dump, standby rudder on!"

Break in upstairs every afternoon.

When I was a little kid, dad would spread his stuff out for recurrent training on the dining room table. Forget toys. That was COOL stuff. I can still read off some memory items. The 727 is on the list of airplanes I'm sorry I never got to fly.

 

[derg]

NO GREEN LIGHT!!! NO GREEN LIGHT!!!

 

[dasleben]

Break in upstairs every afternoon.

When I was a little kid, dad would spread his stuff out for recurrent training on the dining room table. Forget toys. That was COOL stuff. I can still read off some memory items. The 727 is on the list of airplanes I'm sorry I never got to fly.

Some places still fly them.

 

[derg]

Break in upstairs every afternoon.

When I was a little kid, dad would spread his stuff out for recurrent training on the dining room table. Forget toys. That was COOL stuff. I can still read off some memory items. The 727 is on the list of airplanes I'm sorry I never got to fly.

I still have all of my manuals and gouge.

Dad teach you the "Little U Big U" flow?

 

[seagull]

TETO EO, 1-3-2-E-E-1-2-3

I think I can even still draw the electrical system from memory!

Easy P spreads VD was another one.

 

[Autothrust Blue]

Some places still fly them.

Oh yeah, I know...

I still have all of my manuals and gouge.

Dad teach you the "Little U Big U" flow?

FE panel pre-start, right? I don't remember where it starts or ends, but if you gave me 20 minutes with a CPT/paper tiger I could probably set it up. Talk about primacy!

If flaps are extended, one, or both, packs off...

 

[meritflyer]

Here is an except from Part 25, Certification of Transport Category Airplanes. Testing the aircraft in straight sideslips is part of the certification requirements of the airplane down to speeds of 1.13Vsr1:

§ 25.177 Static directional and lateral stability.
(a) [Reserved]
(b) [Reserved]
(c) In straight, steady sideslips, the aileron and rudder control movements and forces must be substantially proportional to the angle of sideslip in a stable sense; and the factor of proportionality must lie between limits found necessary for safe operation throughout the range of sideslip angles appropriate to the operation of the airplane. At greater angles, up to the angle at which full rudder is used or a rudder force of 180 pounds is obtained, the rudder pedal forces may not reverse; and increased rudder deflection must be needed for increased angles of sideslip. Compliance with this paragraph must be demonstrated for all landing gear and flap positions and symmetrical power conditions at speeds from 1.13 VSR1 to VFE, VLE, or VFC/MFC, as appropriate.
(d) The rudder gradients must meet the requirements of paragraph (c) at speeds between VMO/MMO and VFC/MFC except that the dihedral effect (aileron deflection opposite the corresponding rudder input) may be negative provided the divergence is gradual, easily recognized, and easily controlled by the pilot.