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Thread: Emergency brakage improvements

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    Default Emergency brakage improvements

    As far as I know, a substantial part of passenger aircraft crashes are because the brakage is not as sufficient as needed (overruns runway). The reasons may be a failure of wheel brakes or aerodynamical brakes, failure of an engine or lack of fuel, what makes impossible using the reverse. Other reasons may be failures that enforce greater speed of landing approach or problems with precise steering that can cause landing too close to the middle of runway. Or if is necessary to land on a little airport, which has no sufficiently long runway. Or on the highway, which has viaducts limiting the "runway" length.


    That's why I propose two emergency methods of braking.

    1. In military aircrafts and in space shuttles braking parachutes are in use. Passenger aircraft could have such a parachute for emergency use. The stewardess should be able to launch it if launching from the cockpit is impossible.

    2. Airplanes prepared to land on aircraft carriers have a hook which catches a rope that gives an additional braking force. This could be used during emergency landing of passenger airplanes. If we don't want to make a special hook at the bottom of the airplane, we can choose two ways:
    - a rope should be located just below the nose of the airplane and catch the crus of the front wheel of the plane; the rope should be spooled on two spools, able to relieve the rope with a resistance (and convert the energy of the aircraft into heat). This is disputable whether the resistance should be fixed or automatically adjusted to situation - if anybody wants it, I will post my ideas about how to adjust it. The spools should be prepared by the airport crew either at the beginning of runway or about its middle, depending on whether there is a danger of landing near the middle of the runway. There should be several sites near the runway, where the spools could be anchored.
    - as above, but the rope should be stretched above the nose of the plane. This requires a special construction of the aircraft: the vertical skeg should have a hook, or an extra hook could be exserted by the aircraft crew before the landing.

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    Quote Originally Posted by Adam_23 View Post
    As far as I know, a substantial part of passenger aircraft crashes are because the brakage is not as sufficient as needed (overruns runway). The reasons may be a failure of wheel brakes or aerodynamical brakes, failure of an engine or lack of fuel, what makes impossible using the reverse. Other reasons may be failures that enforce greater speed of landing approach or problems with precise steering that can cause landing too close to the middle of runway. Or if is necessary to land on a little airport, which has no sufficiently long runway. Or on the highway, which has viaducts limiting the "runway" length.


    That's why I propose two emergency methods of braking.

    1. In military aircrafts and in space shuttles braking parachutes are in use. Passenger aircraft could have such a parachute for emergency use. The stewardess should be able to launch it if launching from the cockpit is impossible.

    2. Airplanes prepared to land of aircraft carriers have a hook which catches a rope that gives an additional braking force. This could be used during emergency landing of passenger airplanes. If we don't want to make a special hook at the bottom of the airplane, we can choose two ways:
    - a rope should be located just below the nose of the airplane and catch the crus of the front wheel of the plane; the rope should be spooled on two spools, able to relieve the rope with a resistance (and convert the energy of the aircraft into heat). This is disputable whether the resistance should be fixed or automatically adjusted to situation - if anybody wants it, I will post my ideas about how to adjust it. The spools should be prepared by the airport crew either at the beginning of runway or about its middle, depending on whether there is a danger of landing near the middle of the runway. There should be several sites near the runway, where the spools could be anchored.
    - as above, but the rope should be stretched above the nose of the plane. This requires a special construction of the aircraft: the vertical skeg should have a hook, or an extra hook could be exserted by the aircraft crew before the landing.

    Wait a second here, are you really a German fellow that we all know so well?

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    Quote Originally Posted by Adam_23 View Post
    1. In military aircrafts and in space shuttles braking parachutes are in use. Passenger aircraft could have such a parachute for emergency use.
    I can think of two airliners that came with a drag chute. Your homework (should you choose to accept it) is to find out which ones. There may have been others, but I can think of two right off the bat.

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    Quote Originally Posted by ATLcrew View Post
    I can think of two airliners that came with a drag chute. Your homework (should you choose to accept it) is to find out which ones. There may have been others, but I can think of two right off the bat.
    For years, various airport information regarding the Flyover International Airport mentioned arresting cables on 12R/30L, but more recently that seems to be lacking and I ass-ume, they have been removed.

    I also ass-ume that the loss of TWA and National Guard, retirement of F-4's and a reduction in F15/18 stuff rendered them 'largely not needed'.

    EDIT: Wrong

    Quote Originally Posted by AirNav.com
    ...A-GEAR: A-G ARE KEPT IN RECESSED POSN TIL REQ FOR USE. TWR MUST BE NOTIFIED AT LEAST 5 SEC PRIOR TO ENGAGEMENT SO THAT CABLE MAY BE RAISED...
    Just need to start installing tail hooks on airliners...
    Last edited by 3WE; 04-11-2017 at 05:51 PM. Reason: 3BS Wrong as usual
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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    Senior Member Evan's Avatar
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    There are all kinds of structural engineering problems involved in catching a plane by the nose gear. Even with a spooled cable it would probably overload the fuse pin and break off the airframe. The best idea I've seen is what's called an arrestor bed, basically a crushable surface beyond the runway that has the effect of running into soft soil. That slows it down rapidly without a gear collapse.

    https://en.wikipedia.org/wiki/Engine...rrestor_system

    Please no more parachutes. The last thing you want is an accidental parachute deployment in flight...

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    Quote Originally Posted by Evan View Post
    ...The best idea I've seen is what's called an arrestor bed, basically a crushable surface beyond the runway that has the effect of running into soft soil. That slows it down rapidly without a gear collapse...
    Would that work at Midway, Houston, Dallas, Regan, San Diego?

    I did like the hostie-controlled chute idea.
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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    I have a German surname, but I am not a German, I am a Pole. And tell me, how you discovered my surname; my nick is Adam_23 which is made of an international name. Did you see my email address? I don't see it when reading my post.

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    Well, military aircrafts and space shuttles use braking parachutes. Have there been any accidental launching of the parachutes? If we are affraid of such possibility, we may make so that the rope of the parachute is not locked to the aircraft tail during the normal flight, so if the parachute launches, it goes away. But if we are going to do an emergency landing, the stewardess goes to the tail and moves a lever which locks the rope. I assume the crew usually knows that the landing is going to be abnormal.

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    OK, I didn't know that the crus is so fragile. But we can make a net which will catch the nose of the aircraft (this requires four ropes and four spools, each per one vertex of the net). Or make a hook on the upper surface of the airplane. Probably this is possible for new aircrafts only, not for the existing ones, because the hook must carry a big force. This idea seems better because there is no danger of damaging the engines or the cruses of the middle wheels (as opposite to the front wheel) by the rope.

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    Senior Member 3WE's Avatar
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    Quote Originally Posted by Adam_23 View Post
    I have a German name, but I am not a German, I am a Pole. And tell me, how you discovered my surname; my nick is Adam_23 which is made of an interneational name. Did you see my email address? I don't see it when reading my post.
    Adam:

    1) You burst on to the scene (Post 1.0) with a rather confident suggestion for a fairly radical change to things.

    2) Many of us (me included) have had to learn that lots and lots of interesting and valid ideas have already been considered.

    3) Many of these 'great new ideas' have actually been thought of before, but have not been implemented (or have faded away) because they did not work for a variety of reasons. In some cases, they made things worse.

    4) Runway over runs are one of those items where many potential solutions have been considered. Parachutes and arresting cables have not really worked for airline purposes- ATLcrew's assignment is fascinating, though.

    Summary:

    So, you burst onto the scene with a rather radical suggestion that (unfortunately) has already been thought of before, and really doesn't work that well, and which (sorry flame time) looked crazy-humorous naive.

    We have another poster here (German) who often posts some crazy-humorous stuff. Some of the issue with him is language, but other times, we are not really sure where he was coming from.

    You post seemed kind of similar to our other off-the-wall forum friend who happens to be German- thus the question if you two are one in the same.

    One thing to consider is to maybe take your ideas and convert them into questions:

    Is there some reason parachutes are not currently used on airliners?
    Is there some reason, flight attendants should maybe NOT have access to pop a parachute?

    I will close with a question to you:

    Does the idea of using a computer and GPS and airspeed indications and other data, to double check to see if the plane is accelerating properly towards takeoff speed, and warning the pilots if the acceleration is amiss sound like a good idea?
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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    Senior Member Evan's Avatar
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    Quote Originally Posted by Adam_23 View Post
    Well, military aircrafts and space shuttles use braking parachutes. Have there been any accidental launching of the parachutes? If we are affraid of such possibility, we may make so that the rope of the parachute is not locked to the aircraft tail during the normal flight, so if the parachute launches, it goes away. But if we are going to do an emergency landing, the stewardess goes to the tail and moves a lever which locks the rope. I assume the crew usually knows that the landing is going to be abnormal.
    Yes, military aircraft and spacecraft allow for a much higher risk factor. Passenger aircraft are governed by certification standards that are far more cautious. The basic rule of thumb in engineering is, when you add safety features, you add complexity, which in turn adds points of failure and potentially creates new risks. So these things have to be very well thought out. I don't think the commericial transport industry would want to mess with drogue parachutes anymore. Absolutely it would be a cockpit-controlled feature, but mechanical error or pilot error at the wrong moment could spell disaster (and I almost guarantee it would happen sooner or later).

    The best minds have worked on this and the best solutions thus far are arrestor beds and, for takeoff overruns, Takeoff Performance Monitoring Systems (TOPMS). Cables, nets, pools, a giant airbag... these are impractical for so many reasons. The thing to do is study aeronautical engineering for eight years—or just general physics—and then you might understand.

    However the BEST way to avoid runway overruns is to prevent them from happening. That is why we now have highly standardized Stable Approach Criteria, automated Instrument Landing System approaches, Wide Area Augmentation System (WAAS) GPS-based approaches and (hopefully soon) Local Area Augmentation System (LAAS) to assure the glidepath always puts your wheels on the touchdown zone and within the safe range of airspeed and sink rate. Training is also getting better (one hopes) to avoid missing critical memory items like checking the ground spoiler deployment and getting reversers out quickly. As in most areas of passenger aviation, the solution isn't to make the thing crashworthy, it is to avoid crashing in the first place.

    But of course there will be failures, such as hydraulic failures where you lose flaps, ground spoilers and reversers and have to make a high-speed landing with wheel brakes alone. Sometimes that's just going to be an overrun. So there must be provision for safe runway excursion whereever possible, where the airplane might get written off but everyone walks away...

    The stuff you are suggesting, people thought of that on day one.

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    Senior Member 3WE's Avatar
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    Quote Originally Posted by Evan View Post
    ...Takeoff Performance Monitoring Systems (TOPMS)...these are impractical for so many reasons...
    Have "we" put TOPMS in the "Good-idea-BUT" folder?
    Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.

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    Quote Originally Posted by 3WE View Post
    Have "we" put TOPMS in the "Good-idea-BUT" folder?
    I haven't...

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