DC-10 final altitude vs others......

From the perspective of someone who lives around 19DME off of IADs 1's and a person who flies into Dulles alot it has to do with style of flying.

I know when we come into IAD if we have the airport 30 miles out, they sometimes will clear us for the visual. Some people will set pattern altitude of 1900 feet and hurry on down and at 20 miles out they are at pattern altitude flying along at 250. Then there are the guys that just intercept the glide slope and follow it down.

Basically the guys who get down to pattern normally like to come screaming in at 250 and just pull the power levers to idle a dot below the slope, get it dirtied and then head down. Then the guys that follow glide slope have to manage speed a little better.

This may be how other airlines do it. I know sometimes I see wide bodies at what seems like pattern altitude right above my house. Then when I go to work I see why.

He didn't say 30 miles out, or 10 miles out, he said 1.5 miles out. At 1.5 miles the plane should be 4-500 ft AGL and completely configured. If you are not completely configured and on glidepath at 500 ft, you are unstabilized and should be going around. I think it has everything to do with an illusion that the MD 11's are so dang much bigger that they look slower and lower than the rj's do.
 
No, but I have been at the controls of a jet aircraft going into MCO landing on 18R on enough occasions to know that they instruct aircraft to maintain 2,500 until south of the ORL VOR. If someone is at a different altitude, they are deviating from their clearance.

You found, read, comprehended and quoted the text from the AIM, but you didn't see the answer to your question?

"Three-bar VASI installations provide two visual glide paths. The lower glide path is provided by the near and middle bars and is normally set at 3 degrees while the upper glide path, provided by the middle and far bars, is normally <sup>1</sup>/<sub>4</sub> degree higher."

I don't know what you're looking for us to say to "disprove [your] supposition". We've all cited practical examples of why we think you may be experiencing an optical illusion, but you continue to doubt us. Aircraft landing on the same runway have absolutely NO reason to be at a different altitude over the same point, regardless of size, parking location, aerodynamics, or anything else.


Ok, you got my attention at the 2500 mins above ORL.

I had wondered if the middle and far bars could be for smaller aircraft to approach with a higher glide path--from your reply--, it makes sense that the 3 degree glide-path is maintained for bigger aircraft while using the middle and far bars and for smaller aircraft with the near and middle bars. I.e it is a sight picture thing, not a glide slope thing.


As for disproving my suppositon,

I stand by my approach--I do not pretend to know things I do not know no matter how many people say things are so; However, professionals who's advice I respect say I am wrong and I need to prove to myself why based on my respect for their (your) argument.

I think you are right--I do not know so--the burden of proof is on me, not you.

When I do so, I will let you know in another post.

And I thank you for your patience.

Cordially,

b.
 
He didn't say 30 miles out, or 10 miles out, he said 1.5 miles out. At 1.5 miles the plane should be 4-500 ft AGL and completely configured.

He didn't say 1.5 miles out either. He said 1.5 miles from the ORL VOR, which, without looking at a map, I believe is 8 miles from MCO.
 
I guess all i can add is, look at a MD-11 and a CRJ next to eachother, that should clear things up.
 
From the perspective of someone who lives around 19DME off of IADs 1's and a person who flies into Dulles alot it has to do with style of flying.

I know when we come into IAD if we have the airport 30 miles out, they sometimes will clear us for the visual. Some people will set pattern altitude of 1900 feet and hurry on down and at 20 miles out they are at pattern altitude flying along at 250. Then there are the guys that just intercept the glide slope and follow it down.

Basically the guys who get down to pattern normally like to come screaming in at 250 and just pull the power levers to idle a dot below the slope, get it dirtied and then head down. Then the guys that follow glide slope have to manage speed a little better.

This may be how other airlines do it. I know sometimes I see wide bodies at what seems like pattern altitude right above my house. Then when I go to work I see why.


Do you think they do it to have a slower descent rate and reduce load on the gear?
 
Do you think they do it to have a slower descent rate and reduce load on the gear?

The gear doesn't know how fast you're descending.

The only thing that matters to the gear is that it isn't extended at any speed faster than it is designed to be hanging in the wind, and that you put it gently on the ground.
 
I'm typing from my mobile, so excuse the spelling, gammar and punctuation errors.I was based in MCO for a couple years flyng EMB145s and EMB135s. Those were always flown on a 3 degree glidepath. At landing speeds, the descent rate was around 600 fpm. You put that jet on the ground 1000 feet from the threshold.Now a couple years later, I fly a 747-400. I fly a 3 degree glide path. At our landing speed that puts the descent rate about 700 fpm. We stay pegged on the 3 degree glideslope.Because the jet is so big and the cockpit is so high, we are on the widebody VASI or using the PAPI appropriately for the wide body. I put (er attempt ;) ) to put the jet on 1000' down the runway.Do the math for a 3 degree glidepath. All planes at the same distance from MCO should be at the same altitiude.
 
Been a while since I've landed at MCO but I use to do it a lot. We always got the clearance to maintain at or above 2500' until south of the ORL VOR when either landing on 18L or 18R. 18R was our preferred rwy due to the UPS ramp location.

We're limited to no more than 1000' ft/min below 1000' and stable while in the final landing configuration. The usual 2500" crossing clearance had the potential of making that approach a little sporty if you were late in getting slowed and configured. You were already high at that point and if you're also fast, well...forget it. The MD11 is even more critical due to it's much higher normal approach speeds of 150+kts.

BTW, we don't land long (outside the touchdown zone). We don't do soft field landings. We don't fly high or low based on where our ramp is located. You get on the VASI/GS and follow it to the touchdown. I basically have 1500' (2500' to 1000") to get on profile after passing south of the ORL VOR and then I'm limited to no more than 1000"/min. If that gets me in the touchdown zone..great! If not, we go around.

I'm pretty sure other 121 carriers follow the same profile constraints so it becomes REAL important that you make the constraint AT 2500' and no higher. What you're probably seeing beyond the "size of the aircraft" optical illusion is some folks who make the crossing higher than 2500". Smaller planes, those with slower approach speeds and T-props have more wiggle room than the heavies.
 
Been a while since I've landed at MCO but I use to do it a lot. We always got the clearance to maintain at or above 2500' until south of the ORL VOR when either landing on 18L or 18R. 18R was our preferred rwy due to the UPS ramp location.

We're limited to no more than 1000' ft/min below 1000' and stable while in the final landing configuration. The usual 2500" crossing clearance had the potential of making that approach a little sporty if you were late in getting slowed and configured. You were already high at that point and if you're also fast, well...forget it. The MD11 is even more critical due to it's much higher normal approach speeds of 150+kts.

BTW, we don't land long (outside the touchdown zone). We don't do soft field landings. We don't fly high or low based on where our ramp is located. You get on the VASI/GS and follow it to the touchdown. I basically have 1500' (2500' to 1000") to get on profile after passing south of the ORL VOR and then I'm limited to no more than 1000"/min. If that gets me in the touchdown zone..great! If not, we go around.

I'm pretty sure other 121 carriers follow the same profile constraints so it becomes REAL important that you make the constraint AT 2500' and no higher. What you're probably seeing beyond the "size of the aircraft" optical illusion is some folks who make the crossing higher than 2500". Smaller planes, those with slower approach speeds and T-props have more wiggle room than the heavies.

That makes sense, thank you!

Another thing I hear (I think) is the heavy jets will be "at idle" and then you can really hear the engines spin up as they intercept the glidepath and maintain it. Due to the fact that the aircraft is moving past me, I wonder if it is just an effect similar to the one when a car radio recedes in the distance. However, It does seem that the DC-10 will come in "low" at idle then just north of my house, hit the gas to speed up/intercept the "glideslope" and then smoothly back off the power. Almost like they want to get low early.

Its really fun to watch and I can tell the DC-10 by sound and "feel" when I am out puttering in the garden. So I go running to the front yard to watch it come in--beautiful thing to see.

Thanks again for the reply.

b
 
Been a while since I've landed at MCO but I use to do it a lot. We always got the clearance to maintain at or above 2500' until south of the ORL VOR when either landing on 18L or 18R. 18R was our preferred rwy due to the UPS ramp location.

We're limited to no more than 1000' ft/min below 1000' and stable while in the final landing configuration. The usual 2500" crossing clearance had the potential of making that approach a little sporty if you were late in getting slowed and configured. You were already high at that point and if you're also fast, well...forget it. The MD11 is even more critical due to it's much higher normal approach speeds of 150+kts.

BTW, we don't land long (outside the touchdown zone). We don't do soft field landings. We don't fly high or low based on where our ramp is located. You get on the VASI/GS and follow it to the touchdown. I basically have 1500' (2500' to 1000") to get on profile after passing south of the ORL VOR and then I'm limited to no more than 1000"/min. If that gets me in the touchdown zone..great! If not, we go around.

I'm pretty sure other 121 carriers follow the same profile constraints so it becomes REAL important that you make the constraint AT 2500' and no higher. What you're probably seeing beyond the "size of the aircraft" optical illusion is some folks who make the crossing higher than 2500". Smaller planes, those with slower approach speeds and T-props have more wiggle room than the heavies.

Thats pretty much it! The visual into MCO landing south can even be a bit sporty in the "metro", especially since I try to fly the airplane as if I had passengers in the back. I'm pretty sure that we have a lot more room to make it happen than you big guys do though!
 
That makes sense, thank you!

Another thing I hear (I think) is the heavy jets will be "at idle" and then you can really hear the engines spin up as they intercept the glidepath and maintain it. Due to the fact that the aircraft is moving past me, I wonder if it is just an effect similar to the one when a car radio recedes in the distance. However, It does seem that the DC-10 will come in "low" at idle then just north of my house, hit the gas to speed up/intercept the "glideslope" and then smoothly back off the power. Almost like they want to get low early.

Its really fun to watch and I can tell the DC-10 by sound and "feel" when I am out puttering in the garden. So I go running to the front yard to watch it come in--beautiful thing to see.

Thanks again for the reply.

b

The DC-10 is probably at idle thrust for much of the descent depending on how high he was passing the ORL VOR. However, once established on profile (GS, PAPI, VASI, whatever) the engines will have to be "spooled" up in order to maintain speed. The final flap setting produces a lot of drag....a lot more than small piston GA aircraft That's great when you're trying to initially come down and slow down but once on profile a quite a bit of power is required to maintain a constant 7-800ft/min descent rate and speed.

We have to be on speed and engines "spooled" up by 1000' to meet stabilized approach criteria. If not, we are required to go-around. Some operators use 500' in VFR conditions. That's probably why you're hearing the engine noise increase low to the ground as the DC-10 has some rather large barn door flaps and a lot of drag to overcome once on profile. Or, you may just be hearing the pilot correcting for a slightly low speed situation. Takes a lot of power to increase speed just a little if it gets a little low during the approach. There's quite a bit of inertia to overcome at that point. That's also why windshear reports are more critical when flying big jets.
 
Thats pretty much it! The visual into MCO landing south can even be a bit sporty in the "metro", especially since try to fly the airplane as if I had passengers in the back. I'm pretty sure that we have a lot more room to make it happen than you big guys do though!

I have about 4000hrs in the San Antonio sewer pipe!:) The great thing about the Metro or any T-prop for that matter, is the ability to "chop-n-drop" and dissipate energy pretty easily. I still miss that ability!
 
I have about 4000hrs in the San Antonio sewer pipe!:) The great thing about the Metro or any T-prop for that matter, is the ability to "chop-n-drop" and dissipate energy pretty easily. I still miss that ability!

One of the biggest challenges for me (if I ever am given the opportunity to step up to the bigs) will be adjusting to having to perform energy management in a large jet aircraft. I'm thinking the days of doing 246kts until a 6 mile final will be long gone!
 
One of the biggest challenges for me (if I ever am given the opportunity to step up to the bigs) will be adjusting to having to perform energy management in a large jet aircraft. I'm thinking the days of doing 246kts until a 6 mile final will be long gone!

Let me tell you from someone who knows.......If you can fly a Metro, you can fly anything at the majors!;)
 
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