Descent Below VASI on Approach

[Zero1Niner]

Seem to recall a discussion with someone telling me that it was in the FAR's or AIM that it is not permitted to descend below VASI at night on an approach.

I cant find any reference to this in either the FAR or AIM. Anyone have any idea what the deal is with this? Is this a fact or fiction?

[minitour]

91.129 (e) (3) Each pilot operating an airplane approaching to land on a runway served by a visual approach slope indicator must maintain an altitude at or above the glide path until a lower altitude is necessary for a safe landing.

...through language in 91.130 and 91.131, it also applies in class C and B airspace.

-mini

[Zero1Niner]

Originally Posted by minitour

91.129 (e) (3) Each pilot operating an airplane approaching to land on a runway served by a visual approach slope indicator must maintain an altitude at or above the glide path until a lower altitude is necessary for a safe landing.

...through language in 91.130 and 91.131, it also applies in class C and B airspace.

-mini

Thanks Mini! Your like a machine!!

[minitour]

A cybernetic organism. Living tissue over metal endo-skeleton.

-mini

[PA44-LUV]

Originally Posted by minitour

A cybernetic organism. Living tissue over metal endo-skeleton.

Borg?

[poser765]

Originally Posted by PA44-LUV

Borg?

Appocolyptic robot killer from the future.

[minitour]

Originally Posted by PA44-LUV

Borg?

Who is yer daddy...and what does he do?

-mini

[matt152]

Liquid metal.

I wonder why PAPIs are not included in this reg? Anyone got an idea?

[jynxyjoe]

Originally Posted by matt152

Liquid metal.

I wonder why PAPIs are not included in this reg? Anyone got an idea?

I believe when they say "visual approach slope indicator" it is a generic term covering PAPIs and all sorts of weird flashy thingys that indicate your target slope.

[MikeD]

Originally Posted by jynxyjoe

I believe when they say "visual approach slope indicator" it is a generic term covering PAPIs and all sorts of weird flashy thingys that indicate your target slope.

Yes. The term is generic and is inclusive of most of the systems covered here:

http://forums.jetcareers.com/technic...si-review.html

[jynxyjoe]

Originally Posted by MikeD

Yes. The term is generic and is inclusive of most of the systems covered here:

http://forums.jetcareers.com/technic...si-review.html

You again?

Could someone please bring up shock cooling?

[matt152]

Interesting. Thanks for the writeup.

[MikeD]

Originally Posted by jynxyjoe

You again?

Could someone please bring up shock cooling?

One I remember from long ago were guys arguing over falling out of an airplane with no parachute.....how you'd suffer "windburn" of up to 2nd degree burns to exposed skin areas from the freefall wind blast.

[jynxyjoe]

Originally Posted by MikeD

One I remember from long ago were guys arguing over falling out of an airplane with no parachute.....how you'd suffer "windburn" of up to 2nd degree burns to exposed skin areas from the freefall wind blast.

Quickly, someone bring up those POS Cirrus's and their GD parachutes.

Oops, I did it again.

[deadstick]

Originally Posted by jynxyjoe

Quickly, someone bring up those POS Cirrus's and their GD parachutes.

Oops, I did it again.

133 kts to pull the chute? How does that work after a wing falls off at 180 kts?

At an 800' AGL TPA, or at about 500' for that dreaded base-final turn, how far below the ground will the airplane be before the chute is fully deployed?


FYI:
"The minimum demonstrated altitude loss for a CAPS deployment from a one-turn spin is 920 feet."
I love playing the antagonist.

[ghogue]

Originally Posted by MikeD

Yes. The term is generic and is inclusive of most of the systems covered here:

http://forums.jetcareers.com/technic...si-review.html

Mike,
VASI is not generic for the other systems. The generic term is VGSI (Visual Glideslope Indicator) which includes VASI, PAPI, Pulsating Systems, Tri-color Systems, and Alignment of Elements Systems. IOTW, a PAPI is not a type of VASI, it's a type of VGSI.

I know many use VASI in a generic sense, but in a letter from FAA Regional Counsel, they state that the term VASI in 91.175 (visual references for descent below DA/MDA), does not allow for substitution by other systems, to include PAPI.

Gary

[MikeD]

Originally Posted by ghogue

Mike,
VASI is not generic for the other systems. The generic term is VGSI (Visual Glideslope Indicator) which includes VASI, PAPI, Pulsating Systems, Tri-color Systems, and Alignment of Elements Systems. IOTW, a PAPI is not a type of VASI, it's a type of VGSI.

I know many use VASI in a generic sense, but in a letter from FAA Regional Counsel, they state that the term VASI in 91.175 (visual references for descent below DA/MDA), does not allow for substitution by other systems, to include PAPI.

Gary

Its a generic term in the sense of how pilots use it. Not the technical definition. Yes, its a VGSI, but I was referring to the common nomenclature.

Unfortunately for the FAA, and for pilots, many airports have IAPs where there is no VASI, but more often PAPI or one of the other VGSIs (OLS, for instance). In this case a pilot is more than likely going to use that in conjunction with other visual references, and it would be transparant to everyone concerned.

[deadstick]

Originally Posted by ghogue

I know many use VASI in a generic sense, but in a letter from FAA Regional Counsel, they state that the term VASI in 91.175 (visual references for descent below DA/MDA), does not allow for substitution by other systems, to include PAPI.

Gary

Got a copy of the letter?

[calcapt]

Just asking the question: Why would you want to descend below the VASI? Do you need a rule to say that?

[Orange Anchor]

Originally Posted by jynxyjoe

You again?

Could someone please bring up shock cooling?

I'm shocked you would mention it!

[ghogue]

Originally Posted by deadstick

Got a copy of the letter?

This is the one I referred to.

[jynxyjoe]

Originally Posted by deadstick

133 kts to pull the chute? How does that work after a wing falls off at 180 kts?

At an 800' AGL TPA, or at about 500' for that dreaded base-final turn, how far below the ground will the airplane be before the chute is fully deployed?


FYI:
"The minimum demonstrated altitude loss for a CAPS deployment from a one-turn spin is 920 feet."
I love playing the antagonist.

No man. Pull early, pull often. I suggest to my students, if i had any, to just pull it on the taxiway.

[Zero1Niner]

Originally Posted by ghogue

This is the one I referred to.

Curious if this is one of those 'opinion varies by FSDO' interpretations. Seems like every POI on the planet, let alone each FSDO has a different interpretation of the regs.

[Realms09]

Originally Posted by calcapt

Just asking the question: Why would you want to descend below the VASI? Do you need a rule to say that?

This is from the perspective of operating small aircraft on small airfields, but I find it useful to descend below the VASI on very short final. The aiming point provided by the VASI can be relatively far down the runway, with a resulting touchdown point even farther down. Shifting the aiming point closer to the threshold results in a lot less "runway behind you."

[BajtheJino]

Originally Posted by calcapt

Just asking the question: Why would you want to descend below the VASI?

To make a closer taxi way.
I used to land at night at this particular field with great vis, no obstacles yada yada yada. I would come down on the Vasi all red. No problems, no near collisions. Touched down just past the white line and was off on the nearest taxi way. The next one was about 2000 feet down which would mean an extra mile of taxi. F that.