360 and 450 degrees high overhead approach techniques

[wildbillkelsoe]

In Rattler 1-7 and Chickenhawk, authors describe a high overhead approach as their favourite MO in 'Nam. Any pointers or reading material on how to perform these types of approaches?

 

Thanks

[helonorth]

You can make you approach as steep as you want but watch out:

 

http://www.copters.com/aero/settling.html

 

I guess maybe you talking about some kind of spiraling approach? Wally can probably be of help.

Edited June 26, 2016 by helonorth

[zippiesdrainage]

Basically it's the same technique a lot of EMS pilots use in heavily mountainous terrain. You still try to do a normal approach angle but because of the mountains it makes it difficult to keep your LZ in sight at all times. The real only alternative is to slowly descend as you make a wide circle over your LZ and until you're finally low enough that you can straighten out and finish the last short final in a straight in fashion.

[Wally]

Two procedures vaguely remembered fit the term:

 

The first was an instrument procedure where you DF homed, crossed the signal, turned to the signal, homing and descending, repeat as necessary making figure 8s until you broke out or chickened out. Never did this as an IFR procedure.

 

The second required locating the LZ, over-flying it, and initiating a rapid descent, turning and decelling into the LZ. No part of this needed to be flown straight and kept you in sight of your point at all times. This is the quickest way from cruise to landing that I know of- with practice. The disadvantage is that you are in sight of the LZ at all times and can build a high descent (not all bad) pulling a little g in the turns. Moderate turns and descents, and it's my favorite approach.

Edited June 26, 2016 by Wally

[REdge]

As a slick driver in the 70's, it was a SOP maneuver for the 162nd, I remember over flying the LZ at 1,000-1,500' in a left echelon or heavy left, calling "break" with a 5 sec interval. Right Bank to 20 degree, 10%tq, 60k attitude and elongating the last 180 degree of turn with further deceleration to establish final while sequencing in for landing. Not a good thing for large flights but 2-3 ship, day VFR works well to limit small arms fire exposure ahead of an LZ. Used it in a Hawk Somalia for embassy pad descents as well as in AFG in Huey-IIs for select FOB arrivals. Just another tool in the tactics box and it has it's place.

[kona4breakfast]

Hang out near an air force base with fighters, they do it all the time. Just faster.

[Gomer Pylot]

It was standard in the UH1 back when, and standard for landing at scenes when flying EMS. The degree of urgency varies, as does the aggressiveness of the maneuver, but it's essentially the same. In EMS nobody is likely to shoot at you, and there isn't a huge hurry to get down, but the overhead approach satisfies the requirements. I need to see the scene, check for obstacles, the wind, and where the ambulance is. I can see all that somewhere in the circle, usually all through it, and the object is to end up at the optimum approach direction and angle, considering all the above. It's certainly not an aggressive maneuver, and not done too close to the LZ, and the speed is kept relatively slow. I like ~60 kts, almost never below that until on final. The rate of descent is whatever it takes to get on final at about 300' AGL, and I tend to keep that rate of descent until I get near where there could possibly be wires. I don't mind a 300 fps descent at 300'AGL in flat terrain, but when I get near 200' I slow to a very slow rate, because there is always a high probability of wires down lower, and I want a chance to stop the approach immediately if necessary.

 

But that's not the same in a tactical military situation. You worry about what is most likely to hurt you. Rapid descents, in close, with a hard flare at the bottom, is less likely to hurt you than ordnance flying through the chariot. The maneuver is similar, but not completely identical.

[wildbillkelsoe]

Thanks for all replies. How do you determine wind from high reconnaisance? I mean are there signs of controllability that occurs specifically with wind pattern?

[Nearly Retired]

No offense Wild Bill, but if you wait until the start of the approach to start thinking about the wind, you done f'ed up. The time to start thinking about the wind at the LZ is at takeoff from the departure point.

[Gomer Pylot]

Sometimes the winds are light and variable, and sometimes they change. I've seen 180 wind direction changes happen while I was on final. But Bob is right, under most circumstances you should know the wind direction before you arrive, from flags, smoke, groundspeed, drift off course, and other signs. You should always be aware of the wind direction and speed. As you make the circle, you should be able to find the wind direction from the shape of the circle, how you're blown as you go through the maneuver. Sometimes a contact on the ground will tell you the wind. Sometimes the ground contact will be clueless and give you entirely bogus information. All this is why you need to learn how to determine the wind in flight, and keep track of it constantly. With GPS, there is no excuse not to know it. You're given precise groundspeed and course information, so you should know what wind correction you're using and whether you have a tailwind or headwind. You may not know it down to the knot or degree of direction, but you should know the general direction and whether it's strong or light. If you don't keep track of this, you are not a competent pilot.

[Wally]

How can you NOT know where the wind is and be a real helicopter pilot???

You should know at the very least which quadrant of the compass the wind is in at takeoff up date data as you travel- smoke, dust, flags, waves on the water (13 years in the Gulf pre-disposes me to this method, although I no longer remember the Beaufosrt Scale), even leaves and other vegetation, you know "amber waves of grain". Confirm it in your high recon and adjust for local conditions, valleys, buildings, etc.

 

To me, the most important point in planning the approach is having a survivable forced landing area in reach. Another plus for the overhead approach.

[Nearly Retired]

Wally and Gomer, I agree. I'm surprised at how many helicopter pilots I've flown with who cannot even tell me from which *quadrant* the wind is blowing! And I'll even cut them some slack: "Okay, north-ish? South-ish? What?" And it's like once they get in the air the wind ceases to be a factor.

 

I guess it's our GOM experience that makes us more sensitive to the wind, eh? I may not be able to tell you exactly, but I can tell you within 45 degrees or so.

 

Once, I was flying a "field ship" for Shell Oil, a ship that's based offshore every night. One morning, a guy came out from the beach, headed for my platform. On the FM, he asked which way the wind was blowing? Now, it was blowing strong enough to "see" it on the water. I keyed up and, being Mr. Smarta$$ said, "Which way would you land if your engine quit?" He probably still thinks I'm a dick. And... he's probably not wrong. Hope that wasn't either of you, Wally or Gomer ;-)

[Wally]

Wally and Gomer, I agree. I'm surprised at how many helicopter pilots I've flown with who cannot even tell me from which *quadrant* the wind is blowing! And I'll even cut them some slack: "Okay, north-ish? South-ish? What?" And it's like once they get in the air the wind ceases to be a factor.

 

I guess it's our GOM experience that makes us more sensitive to the wind, eh? I may not be able to tell you exactly, but I can tell you within 45 degrees or so.

 

Once, I was flying a "field ship" for Shell Oil, a ship that's based offshore every night. One morning, a guy came out from the beach, headed for my platform. On the FM, he asked which way the wind was blowing? Now, it was blowing strong enough to "see" it on the water. I keyed up and, being Mr. Smarta$$ said, "Which way would you land if your engine quit?" He probably still thinks I'm a dick. And... he's probably not wrong. Hope that wasn't either of you, Wally or Gomer ;-)

Yeah, that was probably me- the only pilot in the GoM who didn't know where the wind was and the only smart-aleck in the GoM answering the radio.

 

P.S. In my opinion, figure-8s before the high recon work even better than drifting circles. Especially with GPS.

Edited July 6, 2016 by Wally

[Gomer Pylot]

Again, I can think of reasons for calling and asking which way the wind is blowing at the destination. Sometimes you know a front is coming or going, and you want to know where it is, or something else makes you uneasy about what might be sneaking around out there. But that isn't the norm, and absolutely shouldn't keep you from knowing the wind where you are.

[r22butters]

Knowing where the wind is coming from. Hmmm, its 2016,...isn't there an app for that yet?

[Nearly Retired]

Gomer, like all of us who worked in the GOM for any length of time, I saw some pretty strange weather. I've seen what I call "frontlets" for lack of a better term. They usually happen on fairly calm, clear days, and mostly in the fall/winter. The wind will be "generally" out of the north, say. Then you go across a line (which may or may not be visible on the water) and the wind is 180 degrees out. You *might* feel a little *bump* going through the change in air mass if you're paying attention.

 

I was doing a rig crewchange one morning in a 206L-1. On the first two flights the wind at the rig was out of the north. Coming out from the beach with the third load, without thinking I set the approach up to land to the north as before. I was talking to the guy in the front-left, telling him what a great pilot I was, not really paying attention. Then, as I got down really close, I finally noticed the windsock indicating a goddam SOUTH wind. It was too late to bail and go around. Jiminy Christmas! Talk about pucker-factor! I'm not exaggerating when I say I'm lucky I didn't crash - and I don't know how I didn't. I'd say God was watching out for me that day, but a certain lady R-44 pilot would be all over my ass like white on rice.

 

After my heart rate came back down from that of a parakeet to a normal human, and after I pried the seat cushion out of my butt, I looked around. There was no obvious indication that I was in a different air mass... No clouds, and no noticeable temp change. And it was one of those days when you really had to look at the water to see the direction. (Velocity is easy - but figuring out whether it's coming from thisaway or thataway can be tricky if there are no whitecaps.) Learned a valuable lesson that day!

 

So yeah, there are valid reasons for asking about wind direction prior to getting out into a field, even on a clear, nice day. Even when you *think* you know where it's coming from, you're sometimes very, very wrong.