Jump to content
Sign in to follow this  
Ed Cesnalis

Unstable approach

Recommended Posts

Airbus A-320

 

Just for the record, I did not see anything unstable about that approach and landing at all.

 

The crew actually did a very good job.

Share this post


Link to post
Share on other sites

Perhaps I don't understand the definition of an unstabilized approach. My point was that he was maneuvering instead of flying a glidepath down the extended centerline.

 

Can you fly a stabilized approach if you need to maneuver on short final?

Share this post


Link to post
Share on other sites

Sure why not, so long as it is controlled and stable.

 

I do know what you meant though. It wasn't a nice straight in setup style approach.

Share this post


Link to post
Share on other sites

Perhaps I don't understand the definition of an unstabilized approach. My point was that he was maneuvering instead of flying a glidepath down the extended centerline.

 

In general, with reference to air carrier operations, stabilized approach means, by 1000 ft. agl, the airplane is: on speed, configured (gear and flaps), on glidepath (if one is available) and descent rate is normal (no more than 1000 fpm max). Additionally, engines spooled up by 500 ft. (not at idle). Some companies may require those criteria earlier than that. Anything outside those parameters is considered "unstable" and a go-around is mandatory.

 

Can you fly a stabilized approach if you need to maneuver on short final?

 

Absolutely. There are special exceptions to the above conditions sometimes.

 

One example of that is flying into Ronald Reagan Airport (formerly Washington National) and landing to the south on runway 18.

 

Once cleared by ATC, the River Visual arrival procedure (about 10 miles long) requires that you fly down the Potomac River, then on short, short final, execute a sharp right turn (which is about 300 feet above the water) to line up with runway 18. Deviation from the river is prohibited. Glidepath info is provided by a PAPI (precision approach path indicator) on the dogleg and final.

 

Places like the video you posted, as well as Reagan Airport, are kind of exceptions to the general rules. But if they are flown well, they are very safe . . . . . and fun!

Share this post


Link to post
Share on other sites

Stable vs stabilized ?

 

Can we say the approach was stable but unstabilized ?

 

Per Airbus at 500' he needed to be stabilized which included '[o]nly small changes in heading and pitch are required to maintain this flight path' by definition.

 

http://www.airbus.co...-APPR-SEQ01.pdf

 

EDIT: I will defer to Wm.Ince's post above. I was impressed by the approach not trying to say there was anything wrong with it, just that it was difficult maneuvering at that very low altitude.

Share this post


Link to post
Share on other sites

Stable vs stabilized ?

 

Can we say the approach was stable but unstabilized ?

 

Per Airbus at 500' he needed to be stabilized which included '[o]nly small changes in heading and pitch are required to maintain this flight path' by definition.

 

CT,

 

IMHO . . . based on the video . . . and what I was taught . . . I think he was stabilized.

 

I have never been in there, but I would be willing to bet, that is the only way to get into that place. In airline terms, it would be classified as an "irregular operation."

 

From their comments in the video, it led me to believe it was their first time in there. Almost all air carriers would require a check airman to accompany a captain, during his first trip there.

 

The departure and climbout must be an "irregular" operation also.

Share this post


Link to post
Share on other sites

Interesting thread. There's another tight approach and that's the approach to runway 18 at Oshkosh. The August issue of AOPA Pilot has the article "Set-up Stall" written by Bruce Landsberg which discusses Jack Roush's crash in his Beechcraft jet in 2010 at Oshkosh. Very relevant article in regards to the discussion here. Although stabilized approaches appear to be possible in tight quarters, it appears that there is no room for error when one is on short final at 500' while doing a tight banked turn with a turbine powered aircraft.

Share this post


Link to post
Share on other sites

I thought these guys did a great job with a difficult approach and landing.

That last little hill off the end of the runway makes that last little turn critical.

They looked stabilized to me.

During the approach they were also being buffeted around with winds.

That last little turn to final was done at 133kts and I know lots of folks that can't do that the first time and they fly heavy metal.

Nice post.

Share this post


Link to post
Share on other sites

Most of my flying career has been based in FL, so perfectly aligned finals were just how it was done.

 

They are still the vast majority of my final approaches.

 

But when I was based at Blue Ridge Skyport, it was obvious an angled final avoided the tallest trees on the straight in path.

 

A video is worth 1,000 words (relevant part begins around 4:20):

 

Share this post


Link to post
Share on other sites

Nice rolling countryside Eddie. Don't imagine you have to worry much about meeting a departing plane coming at you over that hill.

Share this post


Link to post
Share on other sites

Fly just about anything in the Frank Church Wilderness and you'll find similar approaches along all forks of the Salmon river. That was a stabilized approach. Now do the same approach in IMC. :)

Share this post


Link to post
Share on other sites

Hello from Austria !

I cannot contribute to the technical questions of the Approach, however I enjoyed the Video on flying into Paro Airport very much. Flew in on one of Drukair`s A 319 (Royal Bhuthan Airline)a couple of years ago for a hiking trip and it was exciting! Felt more like flying into one of our mountain airfields in my CTLS than in an Airbus - following deep Valleys, up to 16000ft peaks around and sometimes flying VERY close to the ground with marvelous views of Buddhist monasteries.I was assured there were only few pilots certified to land at Paro.

Thanks again for the Video!

Anselm

Share this post


Link to post
Share on other sites

CT,

 

IMHO . . . based on the video . . . and what I was taught . . . I think he was stabilized.

 

I have never been in there, but I would be willing to bet, that is the only way to get into that place. In airline terms, it would be classified as an "irregular operation."

 

From their comments in the video, it led me to believe it was their first time in there. Almost all air carriers would require a check airman to accompany a captain, during his first trip there.

 

The departure and climbout must be an "irregular" operation also.

 

I think the narration was by the photographer in the jump seat and he sounded like he hadn't been there before. I would hope that at least one of the pilots was experienced landing there.

 

Nice job!

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×