Obstacles Surrounded Airports

[Fropilot]

I would like to hear from pilots who operate or have operated into difficult airports. I would like to know how other pilots and operators who need and have to operate into obstacle surrounded airports of various types approach these issues. Particularly when the only alternative would be to, not operate or nuke mountain.

[Old Smokey]

Much more information needed!

If you're VFR - Look out and live.

If you're flying an FAR25 aircraft (or it's equivalent), do a FULL obstacle analysis and establish suitable escape routes, ALL Engines, and OEI.

Regards,

Old Smokey

[blackmail]

old smoky is a wise man!

[OzExpat]

I couldn't have said it better myself OS. I'm not at all sure that the stated option to "nuke mountain" would be especially popular with the folks that live there. :}

[autoflight]

There are many airfields where close-in obstacles need proper consideration. There are also many aircraft operators (including flag carriers) that choose to ignore the theory & practices for safe flight.

[mutt]

autoflight

that choose to ignore the theory & practices for safe flight Would you care to expand on this statement?

Mutt.

[Fropilot]

I do not think anybody chooses to simply ignore the theory and practice of safe of flight. If you have no place to build an ideal airport does this mean that your only means should be by donkey and cart or an airstrip albeit with less than generally acceptable airport environment standard.

[Loose rivets]

Anyone remember the hotel at Ibiza c 1970? Just off the centerline. I was told to fly as near to it as I deemed safe. I was young then...I think we conveyed our meaning.

I watched it being blown up on telly one night.

[HSWL]

One 737 company I knew not only did not concern itself with obstacles in the take off flight path, but fiddled the runway analyses by changing the heights of the obstacles that were on State published charts to get better take off weights. This in one case gave the company a 7000 kgs advantage of another operator taking off on the same runway. The regulator had no idea what was going on under it's nose. No problem with that unless you happened to lose an engine at a critical position on take off.

I saw this sort of thing in a Greek island runway where the so called "escape " procedure stopped short of an island situated in the departure splay where the flap retract height was 800 ft if I recall and the published escape track ran through the island.

When the performance engineers of this substantial company were told of the problem, they shrugged collective shoulders and said it was up to the pilot to use his airmanship in avoiding the hill on the island at night or in IMC, and that the obstruction chart issued by the State stopped one mile short of the hill - very convenient. Legal maybe, but not safe.

My guess is that many pilots would probably be unaware of the protected distance applicable to individual runway analyses take off charts and the potential danger of being literally in the dark. Few runway analyses charts print the survey distance on them.

Considering that at max take off weight a 737 could be still at 1000 ft at 10 miles while accelerating on one engine during the flap retraction process, you would assume that pilots would be taking an active interest in the dimensions of the surveyed flight path?

Without that info available on the take off chart, the pilots are in an invidious position. Pilots have to rely 100% on the veracity of the performance engineer's work otherwise they are in serious trouble in event of an engine failure at the wrong time.

[john_tullamarine]

I daresay that the set of airlines sees approaches to performance scheduling ranging from

(a) ignoring everything other than runway length data through to

(b) a complete analysis of escape paths to a point where the enroute phase can commence with full attention to obstacle clearance throughout.

HSWL quotes a figure for height and distance.

Consider that twins, for which the V2 to clean speed split is significant, can see something in the order of 40-50 nm to complete the takeoff through to enroute phase ... sobering, is it not ?

[Old Smokey]

Oh John_Tullamarine, such very refreshing words from the wise. At the risk of repeating myself on these forums, it is the Performance Engineer's MORAL obligation to design OEI escape procedures providing full and complete lateral and vertical obstacle separation until such time as at least, MSA is achieved, thus allowing provision for either a return approach, or further climb to en-route MEA which can be safely achieved within the MSA coverage.

Every airport that I work with makes this FULL provision, even those with 'innocuous' obstacles. Nothing infuriates me more than to see those procedures (as I do every day) terminating in an arrow head, at an acceleration altitude WELL below the MSA. I'm sorely tempted to pull out my indelible marker and pencil in a question mark, or a Death's Head, at the end of the arrow. We all 'take a peek' at other's solutions when approaching a new airport analysis, I was mortified to see one reputable (?) Australian operator's acceleration altitude of 1000 ft end in an arrow head just a few miles short of a 1250 ft hill. Good stuff! J_T, check your PMs, I don't like court cases by advertising which airline and at which place.

Keep the bas***ds honest John_T.

Regards,

Old Smokey

[mutt]

I believe that one of the biggest problems are performance engineers who have never seen the inside of an aircraft cockpit, let alone flown one, combined with an airline mentality that they have no reason to go behind the cockpit door. This leads to a situation where the engineer is extremely happy to design an OEI procedure based on topographical data and computer programs without ever getting to experience what he is instructing a crew to do!


Mutt.

[Old Smokey]

Mutt,

Sadly, so very very true. What more can be said?

Regards,

Old Smokey

[autoflight]

Mutt, see http://www.pprune.org/forums/showthread.php?threadid=102764

[john_tullamarine]

Mutt's comment strikes a chord and I am aware how he sets about trying to overcome that problem.

In my case, many years ago, I was employed by an airline style operation as an engineer with a number of responsibilities including ops engineering. At that stage I held a CPL and thought I had a handle on the operational side.

Some time later I joined an airline as an F/O on F27 and was quite alarmed the first time I saw the end of the runway disappear under the coaming on a critical runway .. with us still on the ground. Over the following months I had a progressive conversion to my now long held views.

Like Old Smokey and Mutt ... either the ops engineers work VERY closely with the operations folk or they need appropriate operational background themselves.

I can recall two similar sized airlines one of which adopted the work closely philosophy .. and that worked not too badly. The other adopted a third philosophy .. viz the "don't you pilots worry too much about this .. we have it under control" .. in my view .. not quite as effective as the competitor's approach.

One of the problems in the real world is that the mighty dollar drives the horse and cart. While it is a fine high ground to seek to be appropriately conservative, the reality is that there is a risk analysis to be done .. real or notional .. when it comes to settling on a philosophical approach to these things.

If you have a sensibly conservative operations management .. as I did with one long standing client .. we espoused the dollar thing .. while being a tad more conservative in the back room.

If, on the other hand, operations and/or commercial management is dollar ruthless, this may not be feasible.

Then again, if I may paraphrase two points which Professor Richard Wood is fond of making...

(a) if you keep doing the same as you did last week .. don't be surprised to get the same sort of results

(b) if you think safety (ie risk controlled to low levels) is expensive .. try an accident on for size.

Having had aircraft with my design modifications crash for unrelated reasons and having been tied up with legal actions as a result .. I opt for a slightly conservative approach to life as an engineer (and pilot) .. not as much sweat .. and I sleep like a baby ..

[Old Smokey]

autoflight,

Now THAT link you provided was to one of the better threads ever running on Pprune's forums. Maybe it should be resurrected every 6 months or so, or made into a Sticky.

John_Tullamarine, you have the power.

Regards,

Old Smokey

[enicalyth]

Dear All

Non-ideal approach and departure?

Re my St Helena posts elsewhere ad nauseam. I thought that the St Helena airport had been sussed but I reckoned without consultants.

First GxC Lxd, then Atxxxs and good old ASSI who reneged on its promises. Our only potential inward investor spent £2M + recceing the island with a view to safe flying with especial regard to Diana's Peak, the Barn and Great Stone Top. Obstacles that with due care and attention actually define the aerodrome patterns and alignments as opposed to the Civil Service obsession with minimising construction effort whilst maximising danger. And then calling that value for money. To cap it all when industry professionals say "That is dangerous" rather than reverting to the original plan these stuffwits say, "Oh! Very well, we'll bolt on an extra 300metres of RESA for you to have your accident in; and dynamite the top off that hill you are so worried about!" Sheesh you can imagine the cost has tripled. Obviously they don't want us to have an airport so we daily expect the USN to do a Diego Garcia on us! (Just joking).

The outcome of the investor's study given perennial trade winds was that one alignment (I'll call it the Peaks) was inadmissable for landing on 3 deg slope and inadvisable for both mist and, (yes and), turbulence. However it was a beaut for take-off. On the other hand a runway almost perpendicular to this alignment, though shorter, was good for approach and overshoot.

ASSI agreed a deviation was appropriate for RESA length on the grounds that analysis of B737 class aircraft runway end excursions neither needed nor justified the excessive earthworks for greater length. Indeed if by shortening available runway length to construct ramparts worthy of Edinburgh Castle made the consequences of runway excursions more difficult for RFF services to tackle.

But the delays imposed by colonial mandarins who have a vested interested in not being shown in the wrong have effectively enforced a potentially unsafe compromise that could kill off the project.

Through the very kind intervention of the three top A320 product line bods I managed to send an unsolicited appraisal to DfID which vindicated the investor's ideas and backed up the similar conclusions of Boeings airport engineers. Presumably being a backward native islander with a bone through my nose and only several 1000's of hours makes no difference. Filed in wastepaper basket.

If eventually pilots over 55 eventually fly into what is at present the putative airport and I am one of them at least I shall be able to reply to the question "Who thought up this blxxdy stupid approach?" Gennelmen, if they do build an airport on Prosperous Bay Plain St Helena it will be on an unsatisfactory alignment at an inappropriate cost with potentially dangerous plates precisely because the Colonial Administration cannot lose face by admitting that they have wasted time and money. I don't know what J_T and O_S make of that but I'd be happy to expand in private in the hope that we may still avoid catastrophe 2000nm from major trauma surgery.

A murrain on the hides of the Men from the Ministries expecially the Department for Idle Dunces and the Campaign Against Aviation. CASA and ASA ain't so bad after all.

Regards E

[john_tullamarine]

Probably needs an evening over a beer when the three of us are next in Sydney ... sounds like an interesting situation similar to others we have seen elsewhere.

[Fropilot]

Does any one know if there are third party organizations that can provide take off analysis other than the airplane manufactures. Would like to know.

[Ranger One]

Paranoia is your friend.

Before operating into a 'difficult' field for the first time, sit down with plates, manuals, perf. schedules, paper and pencil, and run it all through the computer - the one you keep between your ears - as a sanity check. And *assume these guys are trying to kill you*.

Sooner or later you'll be rewarded with a 'what the hell?!' moment at your desk - which is always preferable to an 'oh sh!t' at the end of the CVR...

R1

[john_tullamarine]

Fropilot ...

There are more than a few organisations and consultants around the place to whom you can turn ..

If you can't locate such entities, do give either me, Mutt, or Old Smokey a PM and we can point you in the right direction.

.. and Ranger One has a sensible idea in his last post ... a healthy dose of scepticism and paranoia is good to see in a pilot ... not all younger pilots have such an approach to life, death, and the universe ... but just about ALL old pilots do ...

[Fropilot]

referring to rangers comments, I have been using the little computer between my ears pretty well to all my flying. What I need now is a desktop to validate what is between my ears. Get the point?

[barit1]

Does any one know if there are third party organizations that can provide take off analysis...

Here's one

Edit to remove commercial link .. sorry but we don't run overt links to commercial services other than via paid advertising ..