727 Early high sink rate crashes
Although everyone knows the standard Boeing 737 technique, I am always amazed by the variation in how colleagues actually flare, and in the end result! Flying a mixture of classic and NG also encourages different techniques.
For various reasons the NG is definitely less forgiving in the flare. Recent trips with Ryanair have demonstrated this when paxing. My answer to the Centaurus question, why blip the power, is that increasing power on the 737 also raises the nose. We tried a few blocked elevator approaches a few years ago, with time left over in the sim, which was extremely enlightening.
We actually call the somewhat firm arrival a 'Boeing landing' in my company. The Boeing push as it has been referred to elsewhere and described a couple of posts above by Wiley Dog seems to work for some. At the end of the day passenger perceptions of the landing come way behind considerations of safety and convenience such as taxi distance etc.
In the sim I stick to the standard technique as frankly I am unconvinced about the fidelity of the sim in the flare and anyway there are no pax and cabin crew to worry about.
For various reasons the NG is definitely less forgiving in the flare. Recent trips with Ryanair have demonstrated this when paxing. My answer to the Centaurus question, why blip the power, is that increasing power on the 737 also raises the nose. We tried a few blocked elevator approaches a few years ago, with time left over in the sim, which was extremely enlightening.
We actually call the somewhat firm arrival a 'Boeing landing' in my company. The Boeing push as it has been referred to elsewhere and described a couple of posts above by Wiley Dog seems to work for some. At the end of the day passenger perceptions of the landing come way behind considerations of safety and convenience such as taxi distance etc.
In the sim I stick to the standard technique as frankly I am unconvinced about the fidelity of the sim in the flare and anyway there are no pax and cabin crew to worry about.
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T tail effects- the whole relevant point..
Finally, thanks to Robert Campbell's post, we get to the point...
T Tail, rear biased wing, airflow over tail, high sink rate. airlfow compression and strut effects, localised drag envelope, and g break effects.
Its simple and applies to other T tailers too!
Isn't the rule on the RJ 146 (T tail but wing mounted engines) to add power and that once you start hauling on the stick she's coming down like a lift unless you whap on the the thrust?0
727 -Never get low and slow- an old rule methinks.
Get a T tailer low and slow, and all the adverse factors will combine in one almighty moment- and lead you to disaster- a massive sink rate and then, if you sit their fat and happy and have not rammed on LOTS of power in one go, they will fall over backwards in deep stall.
The high T tail gives more moment arm of authority and better airflow over the elevators authority except during take off and nose high approach- because the tail surfaces ( the horizontal ones) - 'dip' into the wing wash and become less effective. Whereas a conventional low tail dips below the wash in nose high attitude and is thus more effective.
On a certain light buisness jet, there are some lovely angled vanes under the rear end which dip below the wing wake when too nose high and pitch the tail up - as required.
The 727 - like the VC10 - has a very tall tail fin - the vertical empenage - thus delaying the 'dip' performance loss by keeping the elevators higher than they are on say - a Trident a BAC 1-11 or on one of those stubby tailed modern twinjet T tailer feeder airliners that also lack thrust reverse.
In the development years , Boeing, Douglas and Vickers all shared knowledge on the performance issues of the T tail- and the DC-9 had its tail made taller and its horizontal stabilisers made wider as a result.
The Russians knew too- show me a Russian design T tail rear engine jet with a Trident or BAC 1-11 style, short, low stubby T tail- there are none- they all follow the 727 and VC10 type high fin, broad elevator design - with or without end plates on the fin top.
It is not true that desingers are eschewing the T tail these days- as claimed in these posts. Embraer, Bombardier, Lear, Gulfstream - etc all still deploy the efficiency of the T tail- which by the way was invented by a certain Hans Multhopp in 1930s Germany - he worked with Kurt tank and in June 1945 under 'Operation paperclip' was grabbed and sent to the RAE at Farnborough (along with the Horten brothers) until the Americnas grabbed him and gve him a new life in the USA where he made major contributions to US aviation design and lifting body design.
So, the 727 early handling issues were down to power, flaps, attitude and an understandable failure by pilots and the community in general to really appreciate that when the book says add power on approach and make sure you have deployed the lift protective slats, it meant do it and do it big time- not in a drip drip application.
The 727 wing was amazing - what a plane - handled like a dream. Just avoid being wing clean at 180 knots with low power and no anticipation dialled in to the brain. Just like on then VC10 then - or so say those far better experienced than me.
T Tail, rear biased wing, airflow over tail, high sink rate. airlfow compression and strut effects, localised drag envelope, and g break effects.
Its simple and applies to other T tailers too!
Isn't the rule on the RJ 146 (T tail but wing mounted engines) to add power and that once you start hauling on the stick she's coming down like a lift unless you whap on the the thrust?0
727 -Never get low and slow- an old rule methinks.
Get a T tailer low and slow, and all the adverse factors will combine in one almighty moment- and lead you to disaster- a massive sink rate and then, if you sit their fat and happy and have not rammed on LOTS of power in one go, they will fall over backwards in deep stall.
The high T tail gives more moment arm of authority and better airflow over the elevators authority except during take off and nose high approach- because the tail surfaces ( the horizontal ones) - 'dip' into the wing wash and become less effective. Whereas a conventional low tail dips below the wash in nose high attitude and is thus more effective.
On a certain light buisness jet, there are some lovely angled vanes under the rear end which dip below the wing wake when too nose high and pitch the tail up - as required.
The 727 - like the VC10 - has a very tall tail fin - the vertical empenage - thus delaying the 'dip' performance loss by keeping the elevators higher than they are on say - a Trident a BAC 1-11 or on one of those stubby tailed modern twinjet T tailer feeder airliners that also lack thrust reverse.
In the development years , Boeing, Douglas and Vickers all shared knowledge on the performance issues of the T tail- and the DC-9 had its tail made taller and its horizontal stabilisers made wider as a result.
The Russians knew too- show me a Russian design T tail rear engine jet with a Trident or BAC 1-11 style, short, low stubby T tail- there are none- they all follow the 727 and VC10 type high fin, broad elevator design - with or without end plates on the fin top.
It is not true that desingers are eschewing the T tail these days- as claimed in these posts. Embraer, Bombardier, Lear, Gulfstream - etc all still deploy the efficiency of the T tail- which by the way was invented by a certain Hans Multhopp in 1930s Germany - he worked with Kurt tank and in June 1945 under 'Operation paperclip' was grabbed and sent to the RAE at Farnborough (along with the Horten brothers) until the Americnas grabbed him and gve him a new life in the USA where he made major contributions to US aviation design and lifting body design.
So, the 727 early handling issues were down to power, flaps, attitude and an understandable failure by pilots and the community in general to really appreciate that when the book says add power on approach and make sure you have deployed the lift protective slats, it meant do it and do it big time- not in a drip drip application.
The 727 wing was amazing - what a plane - handled like a dream. Just avoid being wing clean at 180 knots with low power and no anticipation dialled in to the brain. Just like on then VC10 then - or so say those far better experienced than me.
Anyone remember the classic flight test picture of the 727 demonstrating a go-around, I think at Renton circa 1963? The nose is pitched up at what appears to be an impossible, well extremely impressive, angle towards the sky. The gear is up and the ground extremely close. It gives pause for thought, given some of the comments on here about flying the aircraft.
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Makes me wonder.
I'm sure many of you have seen that film of ( I beleive it was NASA ) 727 test landing, where the tail + last few meters of empennage is ripped off, due to excessively high sink.
The test being conducted was a high sink landing thing, except that the pilot exceeded parameters.
I am wondering whether the test was done because of the specific problem with the 727 discussed here ?
( i.e. research into the causes...)
I'm sure many of you have seen that film of ( I beleive it was NASA ) 727 test landing, where the tail + last few meters of empennage is ripped off, due to excessively high sink.
The test being conducted was a high sink landing thing, except that the pilot exceeded parameters.
I am wondering whether the test was done because of the specific problem with the 727 discussed here ?
( i.e. research into the causes...)
I think that with the numbers of Bombardier and Embraer RJs built in recent years (over 1,000 of each), plus the previous generations still in service, there are probably more T-tails in service now than at any time in previous decades.
Those early 727s would have been handled by high time DC6 etc crews, maybe even dating back to WW2 experience. The RJs nowadays are often crewed by those on their first airline position. Yet those early 727 difficulties are not encountered. Reason ?
An analysis I saw many years ago about the early 727 accidents and the subsequent investigation stated that even the test pilots found they were getting caught out in certain circumstances, apart from one guy who was ex-Navy with carrier landing experience. I wonder what that experience was that aided him ?
When I first met Russians they talked about how Russian crews made such good landings compared to BA on the A320, which I regarded as so much nonsense. After quite a lot of exposure to Tu154s since then I can tell you that every single landing has been a greaser, it really is quite amazing the difference in landing capability. I wonder if anyone can attempt a justification.
I believe the film you are referring to was actually the MD-80 prototype in October 1979 at Edwards AFB, which had an FAA crew handling it at the time and which did indeed exceed the design sink rate (not that it looked like that in the film, I have to say). McDD repaired it and attempted to deliver it to customer Swissair, who refused to have it. Nor would anyone else, after about 10 years it was broken up.
Those early 727s would have been handled by high time DC6 etc crews, maybe even dating back to WW2 experience. The RJs nowadays are often crewed by those on their first airline position. Yet those early 727 difficulties are not encountered. Reason ?
An analysis I saw many years ago about the early 727 accidents and the subsequent investigation stated that even the test pilots found they were getting caught out in certain circumstances, apart from one guy who was ex-Navy with carrier landing experience. I wonder what that experience was that aided him ?
We actually call the somewhat firm arrival a 'Boeing landing' in my company
I'm sure many of you have seen that film of ( I beleive it was NASA ) 727 test landing, where the tail + last few meters of empennage is ripped off, due to excessively high sink.
Last edited by WHBM; 11th Jul 2008 at 11:58.
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T tail flying skills
WHBM makes a very good point- those early crews were by historical fact, all ex prop men. They were used to nose down approaches, prop wash over the wings providing lift at low power settting, and had never encountered a 727 wing -the one that unpacks itself so that its slats and flaps hang off it like clothes on a washing line. And they and the rest of the pilot community had very little knowledge of the T tail and rear cg, rear engined handling characteristics.
the ex navy carrier pilot would of course have ben traiend in long jet powered, full flap nose high approaches onto carrier decks - that's why he was ahead of his prop history companions. Phantoms perhaps? Or soemthign earlier maybe.
Glider pilots have an analagy with the T tail low and slow- not -rule - never let the speed drop off on finals, never turn late and slow with a low airspeed - uses attitude and speed brakes as a throttle. add speed on finals -especially in a strong ehad wind- kep the wing loaded with lift and energy.
the ex navy carrier pilot would of course have ben traiend in long jet powered, full flap nose high approaches onto carrier decks - that's why he was ahead of his prop history companions. Phantoms perhaps? Or soemthign earlier maybe.
Glider pilots have an analagy with the T tail low and slow- not -rule - never let the speed drop off on finals, never turn late and slow with a low airspeed - uses attitude and speed brakes as a throttle. add speed on finals -especially in a strong ehad wind- kep the wing loaded with lift and energy.
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Used to fly with a captain at the National, all approaches were flown at vref+15...than he would put on wind additives, when I asked him about it, he said there were a lot of early 72 crashes from high sink rates (I think it was the unspooled engines). Made for exciting approaches at the old SRQ and FMY airports.
I've just looked at the dates/times of the five accidents referred to at the start, and all five appear to have happened during darkness, something we have not touched on previously.
Also, look at that high time but very low jet experience of the skippers.
UA Chicago : 17,142 hours, 82 hours on type.
AA Cincinnati : 16,387 hours, 225 hours on type.
UA Salt Lake : 17,743 hours, 334 hours on type.
PA Berlin : 14,212 hours, 59 hours on type.
Also, look at that high time but very low jet experience of the skippers.
UA Chicago : 17,142 hours, 82 hours on type.
AA Cincinnati : 16,387 hours, 225 hours on type.
UA Salt Lake : 17,743 hours, 334 hours on type.
PA Berlin : 14,212 hours, 59 hours on type.
That is a very insightful analysis. I remember an amazing article in Flying magazine by Len Morgan describing his 720 transition, which was basically self taught. As he put it he had never reached cruising altitude in the airplane, before he first flew with passengers. Nothing unusual there I hear you say. But remember there was no sim and the training was done in the airplane. He was then assigned the least popular base being the old Denver airport (short runway) in the middle of winter! No namby pamby line training. Having survived that he felt pretty qualified.
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Slc 727
If I remember correctly, the UAL SLC 727 accident involved the pilots getting into the nose high, high sink attitude at a rather high altitude.
The deep stall and blanked T tail and engine inlets were just starting to be discussed at the time. I do know that ADs were flying out of OAK city, and there was talk of grounding the 727 fleet. I don't remember if they were grounded, but at least 10kts were added to all minimum airspeeds.
I was flying night freight from SFO and LAX to SLC and PHX in DC-3s at the time. We used to eat at a coffee shop that was very close to the approach end of 25R at LAX. We'd watch the freighters landing while having breakfast at 2AM.
On two occasions I remember seeing UAL 727-100s just about fall out of the sky during the last 100 ft. or so of the descent, the engines finally spooling up enough to save the landings.
I have a friend who flew with me at the Otis Spunkmeyer DC-3 operation. He retired from PSA with seniority #1 just before US Air took them over. His favorite airplane was the 727-100 which he got into from the Electra. He's over 80 now. I'll call him and find out what he remembers.
The deep stall and blanked T tail and engine inlets were just starting to be discussed at the time. I do know that ADs were flying out of OAK city, and there was talk of grounding the 727 fleet. I don't remember if they were grounded, but at least 10kts were added to all minimum airspeeds.
I was flying night freight from SFO and LAX to SLC and PHX in DC-3s at the time. We used to eat at a coffee shop that was very close to the approach end of 25R at LAX. We'd watch the freighters landing while having breakfast at 2AM.
On two occasions I remember seeing UAL 727-100s just about fall out of the sky during the last 100 ft. or so of the descent, the engines finally spooling up enough to save the landings.
I have a friend who flew with me at the Otis Spunkmeyer DC-3 operation. He retired from PSA with seniority #1 just before US Air took them over. His favorite airplane was the 727-100 which he got into from the Electra. He's over 80 now. I'll call him and find out what he remembers.
Last edited by Robert Campbell; 11th Jul 2008 at 15:48. Reason: spelling
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3500 hrs (+/-) 727. Land the plane like any other airplane, no push over, no power in flare, etc, etc. Flare, power at idle at touchdown.
So if the a/c is speed stable, what happens in ground effect if you increase your power?
Used to love watching the 130 kts approaches become the 140kt + landings, past the touchdown zone. 
Ah, but it was a greaser, and the passengers loved it. 
727 had an interesting takeoff rotation. The pitch feel would undergo a slight change, almost like a slight dead spot, during the rotation. You'd rotation, the plane would assume a takeoff attitude, and then sit there for a heartbeat or two before continuing it's takeoff/rotation. I think that's where guys got the saying 'you fly this airplane off the ground'.
So if the a/c is speed stable, what happens in ground effect if you increase your power?
Used to love watching the 130 kts approaches become the 140kt + landings, past the touchdown zone. Ah, but it was a greaser, and the passengers loved it. 727 had an interesting takeoff rotation. The pitch feel would undergo a slight change, almost like a slight dead spot, during the rotation. You'd rotation, the plane would assume a takeoff attitude, and then sit there for a heartbeat or two before continuing it's takeoff/rotation. I think that's where guys got the saying 'you fly this airplane off the ground'.
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Len Morgan's advice
Just checked out Morgan's "Landing the three holer" article in Flying Magazine
Morgan says that with the -200 if it started balloning on touchdown the trick was to ADD power to restore elevator authority and re-land the aircraft. If you cut the power as per so-called 'normal', you lost elevator authority and the thing would start bitching on you - so to speak..
Let's not get into the rut that the 727 was in any way dangerous- it was not - not with over 2,00 sold - and indeed as per by earlier post- like the VC10, due to its very high tail, it could climb at very steep angles -ones that would have condemned a Trident or BAC 1-11 to deep stall regime.
I once went on a LH 727 jumpseat ride out of Frankfurt in the 1980s. 3 crew of course- engineer to help monitor attitude and speed. LH rammed on the power and got the nose well up- all with no drama. On approach they poured on the power -got the Pratt's really pumping. SAS and KLm did the same thing with the DC-9 and then MD 80s (SAS).
Must have cost everyone a fortune in fuel.
Morgan says that with the -200 if it started balloning on touchdown the trick was to ADD power to restore elevator authority and re-land the aircraft. If you cut the power as per so-called 'normal', you lost elevator authority and the thing would start bitching on you - so to speak..
Let's not get into the rut that the 727 was in any way dangerous- it was not - not with over 2,00 sold - and indeed as per by earlier post- like the VC10, due to its very high tail, it could climb at very steep angles -ones that would have condemned a Trident or BAC 1-11 to deep stall regime.
I once went on a LH 727 jumpseat ride out of Frankfurt in the 1980s. 3 crew of course- engineer to help monitor attitude and speed. LH rammed on the power and got the nose well up- all with no drama. On approach they poured on the power -got the Pratt's really pumping. SAS and KLm did the same thing with the DC-9 and then MD 80s (SAS).
Must have cost everyone a fortune in fuel.
I love that line, 'land the plane like any other airplane'. It all seems so easy doesn't it. I seem to remember a well known (and highly respected) parcel carrier wrote a 727 off not so long ago in Florida, during a night landing. The same carrier also operates a large fleet of MD11s a number of which have been written off during landing incidents commanded by highly experienced 727 pilots. You can fill in the caption below the picture of the smoking wreck as you wish, my preference is for 'Shoot bubba, if landing this baby is so easy, what are we doing upside down?!'
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Land the plane like any other airplane
Having flown that ship for 8 years, but yes A340, A320 and A300 are about (!) to land very likely. The 727-200/230 isn't.
Again, as I recall, the airplane stopped well...so much so that the nose wheel brakes were removed by most carriers....not necessary
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Slats One
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Len Morgan's advice
Just checked out Morgan's "Landing the three holer" article in Flying Magazine
Morgan says that with the -200 if it started balloning on touchdown the trick was to ADD power to restore elevator authority and re-land the aircraft. If you cut the power as per so-called 'normal', you lost elevator authority and the thing would start bitching on you - so to speak..
Guys come up with this stuff and it becomes gospel?
Eg, the plane ballons at roughly 120-130 kts(typical landing speeds). But it needs power to restore elevator authority? How did Boeing ever get the plane certified if it lost elevator authority, especially during landing phase?
How did they ever do stalls? Approach to stalls? Slow flight? Stickshaker certification? How did guys ever fly the nosewheel onto the ground, down to speeds as low as 60, 80, or 100kts, if pitch authority was lost during low power operations.
Would guys add power in balloons? It wasn't uncommon to do so, but it's all a factor of how fast you were, how high the balloon was, etc, etc. Adding power had the benefit of an upward thrust vector, which could reduce the potential 'crunch' that might occur if the situation was poorly handled.
The plane had a fair amount of drag. Much more than current generation a/c and would deaccelerate fairly quickly with power off. IMO that's why guys felt more comfortable landing it 'hot' or with power.
It was very unforgiving of any crab on touchdown. Any crab at touchdown, and sideways drift, could make a nice touchdown seem much worse than it actually was.
Today's a/c DC-9, S80, 737/747/757/767/777, A300 are less demanding, but many folks think the 727 was the nicest flying airliner ever built.
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Len Morgan's advice
Just checked out Morgan's "Landing the three holer" article in Flying Magazine
Morgan says that with the -200 if it started balloning on touchdown the trick was to ADD power to restore elevator authority and re-land the aircraft. If you cut the power as per so-called 'normal', you lost elevator authority and the thing would start bitching on you - so to speak..
Guys come up with this stuff and it becomes gospel?
Eg, the plane ballons at roughly 120-130 kts(typical landing speeds). But it needs power to restore elevator authority? How did Boeing ever get the plane certified if it lost elevator authority, especially during landing phase?
How did they ever do stalls? Approach to stalls? Slow flight? Stickshaker certification? How did guys ever fly the nosewheel onto the ground, down to speeds as low as 60, 80, or 100kts, if pitch authority was lost during low power operations.
Would guys add power in balloons? It wasn't uncommon to do so, but it's all a factor of how fast you were, how high the balloon was, etc, etc. Adding power had the benefit of an upward thrust vector, which could reduce the potential 'crunch' that might occur if the situation was poorly handled.
The plane had a fair amount of drag. Much more than current generation a/c and would deaccelerate fairly quickly with power off. IMO that's why guys felt more comfortable landing it 'hot' or with power.
It was very unforgiving of any crab on touchdown. Any crab at touchdown, and sideways drift, could make a nice touchdown seem much worse than it actually was.
Today's a/c DC-9, S80, 737/747/757/767/777, A300 are less demanding, but many folks think the 727 was the nicest flying airliner ever built.