Khe Sanh

[maxdrypower]

Any of you Herc types tell me the flying procedure for a tactical approach believe its nicknamed Khe Sanh approach , Did one once in a herc then a police aircraft but didnt really pay attention to what the pilot was actually doing , anyone care to enlighten me although cant see them allowing them in 172's into Barton

[Runaway Gun]

Only to be flown by experienced Herc pilots I'm afraid, and the technique remains secret. If you try it in a 172 you'll probably ding it - hard.

[Exrigger]

The Khe Sanh Approach
The encirclement of the base meant that there was no safe corridor for the transport aircraft to use for their approach. Any descent towards the airstrip attracted heavy fire from enemy weapons, ranging from infantry small arms up to 12.7mm heavy machine guns and larger calibre anti-aircraft cannon. In order to minimise the risks posed by these hazardous conditions, the transport crews perfected the manoeuvre that came to be known as the Khe Sanh Approach.
A standard landing approach towards a runway would consist of a constant, controlled descent at a shallow angle, but the surrounding hills and risk of enemy fire forced the crews to keep their large, comparatively unwieldy craft (Lockheed C-130 Hercules (http://www.bbc.co.uk/go/dna/h2g2/A4187621/ext/_auto/-/http://www.geocities.com/erlebjorke/landing.jpg), Fairchild C-123 Provider (http://www.bbc.co.uk/go/dna/h2g2/A4187621/ext/_auto/-/http://www.warbirdalley.com/images/c123-02.jpg) and De Havilland C-7 Caribou (http://www.bbc.co.uk/go/dna/h2g2/A4187621/ext/_auto/-/http://www.bragg.army.mil/18abn/images/c-7.jpg))2 (http://www.bbc.co.uk/dna/h2g2/A4187621#footnote2), at a much higher level for longer in order to stay out of range of small-arms and present a smaller target to the larger-calibre weapons. Then, as the aircraft approached the end of the runway, the pilot would drop the nose and put the aircraft into a steep dive, levelling out only at the very last moment. From here, the pilot could either land or make a very low-level pass along the runway at an altitude of about five feet, dropping the supplies out of the open rear cargo doors along the way. The pilot would then pull up sharply at the far end of the runway and execute a steep climb out of the valley, helped by the fact that the plane was now much lighter, having deposited its load.
Such low-level passes could be facilitated by one of two methods. The first was known as LAPES, or Low Altitude Parachute Extraction System, and worked by streaming parachutes (http://www.bbc.co.uk/dna/h2g2/A471179) from the back of the plane as it flew down the length of the runway. These parachutes would be attached to cargo pallets on a roller system in the cargo bay. As the parachute deployed, the pallets would be dragged out of the plane and would eventually skid to a halt, allowing the delivery craft to leave its supplies without touching the ground. This allowed the crew to avoid becoming a stationary target on the runway for enemy artillery, a menace that claimed several aircraft over the course of the siege. This method was eventually discontinued, however, as the pallets did not always come to rest as quickly and smoothly as planned, causing accidents and the deaths of several Marines.
The other, safer method was known as GPES, or Ground Proximity Extraction System. This worked on a similar principle to LAPES, but instead of relying on parachutes to drag the pallets from the plane, they were fitted with a hook that attached to a line stretched across the runway. This had the advantage of bringing the pallets to a virtual stop as soon as they hit the ground. Using these and more conventional higher-altitude parachute delivery methods, the transports were able to supply the 7000 man garrison with 12430 tons of supplies in the course of the 77 days – enough to keep the NVA at bay until the siege was finally lifted.
The Khe Sanh Approach Today
The Khe Sanh Approach is still used today in situations where groundfire is potentially a problem. It was used by coalition forces in the Kuwait conflict and by UN forces in the Balkans, (which led to its alternative name, 'The Sarajevo Approach'). The only modification which has been made to the basic manoeuvre is that the aircraft will now jink from side to side on its approach in order to confuse and evade any potential missile threats.
The technique is also a very popular attraction at air displays and is popular with the display crews of many types of large aircraft, not just the ones mentioned above. It is the Hercules that is the most common performer, though, and it flies in the colours of many different nations. Being a prop-driven aircraft it also has a very distinctive sound, reminiscent of an enormous drone bee dawdling across the sky. With its droopy cockpit 'face' and bulky fuselage it looks ponderous. When it drones lethargically towards the end of the runway, as with every large aircraft on final approach, you wonder why it doesn't just fall out of the air. It is probably travelling at a speed that would embarrass most other forms of transport, yet it blocks out a quite unnerving amount of the sky, seems far too big to be held up by something as insubstantial as air and seems to be hardly moving at all.
Then the pilot drops the nose and your stomach suddenly turns over as this bulky aircraft, helped by the alarming impetus of gravity, goes into an indecently steep dive towards the ground. One of the weirdest things about this is the fact that you get to see the upper side of the wing. With planes this big, this rarely happens. If you see them on the ground, you walk under and around them, always looking upwards. When you see them in flight, you obviously very rarely get to see them from any quarter other than below. Seeing the top half of the Hercules like this therefore feels inherently wrong, especially since the plane is pointing directly at the ground. Like seeing a picture of sinking ship perpendicular in the water or a crashed car upside-down with wheels still gently turning, seeing the unfamiliar upper side of the wing induces a sort of subconscious panic.
The drone of the propellers then increases in pitch as the air now rushing past them makes them spin more quickly and the knot in your stomach rises up to your throat as you realise that the plane is surely going to crash... and then, at the very last moment, the pilot levels out, wheels perilously close to the ground, and makes a pass along the runway, dropping parachuted pallets along its length. It is only as it thunders past your position on the flightline that you realise just how fast it is travelling, and how that dull buzz of propellers and engines is actually a roar. If you are close enough, you will feel the backwash pull at you as the huge, imposing mass punches its hole through the air as it passes, sucking anything not nailed down across the runway in its wake. Then it will climb steeply and within seconds it will be a thousand feet up, banking sharply away, and the roar will revert to a distant drone, the pitch dopplered to a lower and more relaxed note.
It's a pretty spectacular turn.

[microlight AV8R]

If you fancy some steep approaches, try some microlight flying. Various 3axis models are able to make very steep approaches, I presume that their low weight/inertia makes it more practical that heavier GA types. Perhaps somebody with more experience could elaborate?

[Pontius Navigator]

There was an accident to a Skyvan in Oman doing something similar to this.

They were either planning a low level extraction or, given the load of fuel drums, a touchdown and rapid offload.

Anyway the Loadmaster was ahead of the game and had the cargo unfastened and ready to go when the aircraft came under fire on the approach. The pilot initiated a steep climb out but the carge shifted giving an uncontrolable rearward shift of the CofG with predictable and tragic consequences.

[maxdrypower]

no wasnt actually planning to try it was just interested in the technique , how do you remain below flap limiting speed during the steep approach ?

[stickmonkeytamer]

I've experienced it in a C-135FR with the French, because they wanted to see what it was like having read about it on the flight! 707s are not made to do that! Smoking in the cockpit was another concern, but not as much as the ground now filling the cockpit window and the chatter on the headsets was them daring each other as to when they would pull out.:eek: I remember looking out the side of the cockpit at the horizon and thinking that I don't do that large a nose down approach angle in my ickle jet- that was before going out into theatre!!

I've also done the C17 descent into theatre which involves putting the engines into reverse... very sporty!! Those guys can really maneuver their aircraft as well as any small jet- respect due!:ok:

SMT

[microlight AV8R]

I think it's similar to the comparison between microlights and heavier GA types. The momentum is reduced quicker in the lighter aircraft, so the steeper descent is possible due to lighter wieght and consequent reduced speed during descent. steep approaches are common practice in the microlight community.

[Ali Barber]

A very old ex-F4 mate told me about the fast jet version. For them, whenever you turn you almost invariably climb. If you are trying to stay VERY low, the best thing to do is a straight line. 550 kts at 5.5 miles on the extended centre-line, chop the throttles to idle, put the gear and flap down at the appropriate limiting speeds, flare and drop the last few feet onto the runway threshold. To save other people learning the same lesson, it's a good idea to update your nav kit before you try it!

[Tourist]

Maxdry.

1. Every bit of Flap plus gear.
2. Start at just above stall. This gives max pitch change visible from crowd.
3. Throttles closed for max disc effect. (only works on a/c without negative torque sensor.
4. Dump the nose as far as you dare.
5. As flap limiting speed approaches, raise nose to hold speed.
6. Remember to raise nose at bottom(clench!) for two stage flare.
7. Its really important not to forget 6.

This is the show off at airshows version obviously.

[Sospan]

Unless of course you are Italian !!!:}

[Tourist]

They forgot 6.

Great display though!

[Champagne Anyone?]

The microlight has to make a steeper approach as by design, they do not have the stored energy of a spamcan to make a 'normal' gradual decent. They need the increased angle of descent to provide the inertia to keep flying.

:ok: :ok:

[Captain Airclues]

I went for a ride in a Herc in Ascension in 1985 and did a Khe Sanh approach. I later took the Capt and F/O on the 747 sim and we did one at LHR. From 2000ft directly above the threshold we managed to stop on the runway (without any turning).

However, the technique remains secret. ;)

Airclues

[M609]

Unless of course you are Italian !!!

The Italians actually did a dress rehersal for the RIAT crash here at Bardufoss in 97 or 98. Visual approach, Sarajevo style to RWY10. Same a/c type.

Result: Parked main landing gear permantently at the THR, with the rest rolling out and stopping in a snowdrift well to the side of the runway.

[DummyRun]

Quite easy,
Close one eye, stick your tongue out of the corner of your mouth, make it up as you go along and reassure your crew that you heard how to do it once at HH OM EGDL

[Semaphore Sam]

I became an AF pilot in 70...but in my previous existence I was an enlisted puke at Mactan Island in '67-'68. There were two 130 squadrons there...when Khe Sanh developed, our Aerial Port Squadron, and the flying squadrons, became tasked to develop a way to deliver loads without stopping on the runway, because during offloads they were getting nailed...hence LAPES. Practice runs by the side of the runway at Mactan were made for weeks. When first tried at Khe Sanh, loads delivered at high speed would run down guys on the surface (a number killed or seriously injured), until protocols were developed for recovery personnel to stay low until the high-speed pallets stopped moving. There were Marine and AF people at Khe Sanh; at the time it was known that AF personnel were very deep (to avoid incoming, with fridges full of beer); the Marines, brave as they were, were up high...you judge their relative intelligence quotients.

[Kengineer-130]

The best approach I have done was on a mk1 SF Herc into Akrotiri, Cyprus. We had just spent 3 days doing a double engine and prop change, and loads of other jobs to get it back up to scratch. I went on the test flight, as I always jump at a chance to go flying :ok: ;) , and after a few drills (shut-down and re-lights etc), the crew decided to practice an approach that they would be using in a not very nice place later that evening.

All I can say is, when they say steep approach they mean it :D , it went sky, earth,earth,earth,earth,earth,earth, flarerunwaybrakesonstop :} . Awsome bit of flying and just shows what a top bit of kit the old Klassic really is :cool:

Anyway, check out this link to some good herc videos.

http://www.alexisparkinn.com/military_videos.htm

Look at the video marked :C-130 Radical Approach This is the way they routinely land the Hercules in combat zones. Imagine where your stomach ends up? - good vid of a tac approach :ok:

worth a look at them crazy yankees landing on and taking off from an aircraft carrier in a Herc :eek: :eek: :}

[microlight AV8R]

Champers

Thanks for explaining just waht i couldn't seem to get my tongue around :ok:

I have to say that I love steep approaches every time. The workload on final is much reduced in a microlight if you make a steep approach. The steep approach means you can throttle back to idle, a more conventional approach often means more manipulation of power settings to get her there. Fun either way :cool:

[GOLF_BRAVO_ZULU]

Unless a strong thermal just before the boundary leaves you just a few yards of ground to get down in!

[maxdrypower]

intriuging , thanks tourist thats what I wanted , it is fun in a police role equipped islander much fun

[22/7 Master]

I remember sitting rotors running at Bardufoss waiting for fuel when the Italian came in. 2000' descend, looking good, not going to make it so bring the nose up, actually it's looking OK - nose back down Mama Mia not going to make it SMACK! Luckily all the crew were well enough to take the inevitable abuse in Happy Hour.

[LowObservable]

Without trying to start a catfight (Girls! GIRLS!) can the J do a Khe Sanh?

[Samuel]

I've seen RNZAF Hercs do it at a display....still frightens the crap out of me to see such a large aircraft pointing down at such a relatvely low altitude, then it all come right in the end!:eek:

[Green Flash]

The look on the airfield managers face at Fairford was allways worth seeing when we shouted through - 'they're here!':E

[LowObservable]

Ratty,
Just that I remember being told that the digital engine/prop controls would not let you do the low power/fine-pitch props-as-airbrakes routine that is the essence of the Khe Sanh. There's generally not much call for a Khe Sanh in a Saab 2000, which is what the engine was designed for. That may have been fixed... but I have been on board both a K and a J for a tactical landing and I don't remember the latter being quite as energetic.

[YesTAM]

...And if you get it wrong and are very lucky, you just blow tyres.

[Dan Winterland]

...And if you get it wrong and are very lucky, you just blow tyres.

I was a bit luckier than that when a Khe Sanh went wrong. But it was about the closest I've come to be killed in an aeroplane!

[Pom Pax]

Interesting name but how come I saw people practicing something similar ten years earlier? Could it be they were learning from the French's little bit of trouble a couple of years earlier just up the road at Dien Bien Phu?

[Dan Winterland]

Possible, but unlikely. The aircraft used at Dien Bien Phu were C46s, C47s and C119s. All of these didn't have props that were capable of such drag to make such an approach possible. Althought the C46 was slightly better than most as it had an electric actuator controlling pitch.

The French lost a lot of aircraft there. Eventually, when the Viet Cong got close air drops were the only option. The French Air Force didn't have enough airlift capability, so the USA lent them C119s with pilots to fly them. There is a very good book by a pilot called Felix Smith (China Pilot, ISBN 1-56098-398-1) who flew the C119 at the battle. He was an American who flew for an airline called CAT (Civil Air Transport) which was formed after WW2 by Claire Chennault of Flying Tigers fame and was repudedly the most shot at airline in the world. It eventually became the CIA's own airline and Air America was formed out of it. A recommended read.