Science topic

Air Traffic Control - Science topic

Explore the latest questions and answers in Air Traffic Control, and find Air Traffic Control experts.
Questions related to Air Traffic Control
  • asked a question related to Air Traffic Control
Question
1 answer
Respected Sir ,  
      I am kelvin kumar patel rajubhai from Vadodara, Gujarat, India. I am Pursuing M.Tech(structural engineering) from charusat university(CSPIT).My enrollment  (19PGCL006).I have referred your research paper on "Seismic performance evaluation of an ATC tower through pushover analysis". I referred you paper for project validation for ATC tower but in this paper some of the data are missing and also I have problems in making geometry of ATC tower so can you help me to provide any videos of how to make a ATC tower or you geometry to make me easy for my project validation .
      So,I kindly request you to give me your research paper data for my project validation.Your faithful Kelvin Kumar patel rajubhai. 
Here I have attached the research paper in which some of the data are missing or can you provide me data and geometry of ATC tower.
Relevant answer
Answer
ATC Towers are critical for surface movement and take off- landing clearances of the arrival and departing aircraft. So it's construction is with this basic premise of giving it maximum visibility. You can go through these videos for your better orientation.
  • asked a question related to Air Traffic Control
Question
5 answers
I am a master's student in organisational psychology. My dissertation is a systematic review of the measures of workload in air traffic control. This will be a narrative analysis of the findings and implications. Workload in air traffic control is tested under many heterogeneous conditions, which authors have commented prevents from doing a meta-analysis. My analysis will focus on which types of measures (self-assessment, eye movement, EEG, heart rate) have successfully discriminated levels of workload, commenting on the design, methodology and participants in the study, which are often different. Is it possible to borrow elements of meta-synthesis to achieve a structured and comprehensive level of analysis? Thank you!
Relevant answer
Answer
I think reasons not to do a meta-analysis revolve around intolerable differences between studies. Ones that may be mentioned in the literature of your field and proved to make a difference in the outcome. For example, in clinical research different doses of a drug can be a problem, specially if the difference was established in published articles.
To manage these discrepancies, you can do a "subgroup analysis" which makes a separate MA for each set of circumstances and compare each group with certain differences. Or you can do a sensitivity analysis, which involves removing studies that are substantially different (by some defined factor) and see whether removing them makes changes on the pooled estimate. However, it doesn't completely solve the problem, sometimes it's just not a good idea to compare studies using a meta-analysis. If so, try to report results of studies narratively, many systematic reviews are published without MAs. Good luck!
  • asked a question related to Air Traffic Control
Question
12 answers
Automatic Dependent Surveillance Broadcast (ADS-B) is a key avionics technology used for aviation cooperative surveillance (i.e., aircraft separation assurance and collision avoidance). However, the absence of adequate security features makes this system vulnerable to a number of cyber-physical threats (jamming, spoofing, meaconing, etc.). What technological solutions can be introduced to address this challenge?
Relevant answer
Answer
Dear Charles,
Thank you very much for your message and for the valuable documents. I am also very actively involved in this line of research. A recent paper on GNSS performance threats and augmentation strategies in aviation was recently published in JPAS (for convenience, the link is provided below):
In addition to addressing GNSS issues, it would be nice working together and investigating the feasibility of specific safety features that could be included in the ADS-B data-link as well.
  • asked a question related to Air Traffic Control
Question
2 answers
I am trying to perform track-to-track fusion in a asynchronous case. I have great results for monoradar tracks (using IMM (CV, CT, Singer)). But when i starting to fuse tracks I am getting something awful. I do not take into consideration cross-covariances at all. I know it is wrong but these calculations need plots from radars and I have an asynchronous case (periods are different and radars aren't synchronized). How to do it simple and efficient? Is this cross-covariance effect really have THAT huge impact on results?
Relevant answer
Answer
https://confcats_isif.s3.amazonaws.com/web-files/journals/entries/308_0_art_11_27647.pdf - article on Asynchronous Track-To-Track Fusion, though I have not used this article.
What is the difference between the periods of the two radars? Does the prediction of one track sampling time to the other one help, to get to a common sampling time help?
Have you solved the association problem?
For synchronous tracks, I've got good results using the association and fusion equations in article "Multisensor Track-to-Track Association for Tracks with Dependent Errors" - Huimin Chen and Bar-Shalom.
Look for prof. Bar-Shalom articles in the domain, he has some great ones.
  • asked a question related to Air Traffic Control
Question
4 answers
I have found a lot of information about fusion of filtrated tracks but, of course, my tracks were extrapolated before fusion. So I do not have "fresh"  filtration matrices to use them in fusion. I use IMM (banch of 3 KF (CV, Singer, CT models)). Now i use something like that:
1) models probability of i-th model is calculated as mean of model probabilities of i-th model for every connected with global(system) track locals.
2) Covariances( P ): P[i]_system = ( 1/(P[i]_1) + 1/(P[i]_2) + 1/(P[i]_3) ) ^ {-1}
3) coordinates (x): x[i]_system = sum{j=1..3} (P[i]_j^{-1} * x[i]_j) (weighted sum of coordinates for every track)
After that I calculate total covariances and coordinates for the system track:
1) coordinates are just weighted with models probabilities coordinates of every model of system track which were calculated before.
2) Dont know how properly calculate covariances here for systems. Tried some variances but it seems it doesnt work properly.
Have i calculated all properly? How to calculate coordinates having predicted coordinates for all models (already combined)? Any suggestions? Thx a lot.
Relevant answer
Answer
Hello. Fusion of asynchronous radar tracks requires prediction of all track estimates/covariances to the most recent measurement epoch. You wish to calculate the posterior PDF of the target state (assuming no data association problems!) p(x(k) | Y1^k, ... , YN^k ) where Yi^k is the set of measurements from radar i up to time k. You can approximate this PDF using the formulae you provide but you have made a number of assumptions, the most important of which are: (1) the measurements sequences are actually from the target with state x(k); (2) the process noise for each filter is independent. In practice, both these assumptions are violated. There is a fairly simple way to deal wtih (2) on the common process noise. This is covered in Bar-Shalom and Fortmann's 1988 monograph (in the appendix, I think). Your problem is a bit more complicated due to multiple motion models, but that should not deter you! IMM type approximations will help. Good luck. Please upvote if you like this answer.
  • asked a question related to Air Traffic Control
Question
8 answers
All the best
Many thanks
Relevant answer
Answer
Yes,there are already lot of articles on it.
  • asked a question related to Air Traffic Control
Question
5 answers
Hi, 
i'm trying to study which factors encourage or discourage Air Traffic Controllers to fill a safety report in case of aviation incident/accident.
Relevant answer
Answer
Dear Giacomo,
We recently explored the effect of outcome bias on reporting intentions. Whilst our participants were primarily training to work in aviation management, I think what we found might be relevant to ATC too. Gilbey, A., Tani, K., & Tsui, WHK. (2016). Outcome Knowledge and Under-reporting of Safety Concerns in Aviation. Applied Cognitive Psychology. 30(2), 141-151 (If this may be of interest, I can send you a copy if you don't have easy access).
It might be a fascinating topic to research; our study might even work as a template to do so,
Regards,  Andrew
  • asked a question related to Air Traffic Control
Question
4 answers
I am working on ATC target tracking. Using IMM3 (CV, CT, Singer). I get an appropriate quality in the big range situation (When radar measurements have a low accuracy). The problem is i cant get on track fast during maneuveurs. For example: http://take.ms/GYMuB . I dont understand how to fix it. It is not about that I want to describe maneuvers perfectly (I understand that there is some compromise). But I want to return on track after maneuver has occurred faster. In 2-3 iterations. What parameters of filters should i change? May be there is another combination of dynamic models that I should use?
Relevant answer
Answer
Hello. This is an interesting question. There are a couple of Viterbi/EM techniques that you may wish to try. They are compared with IMM in the paper below. You may get some more ideas from the survey paper I did (it was "gazumped" by Li's paper, despite being done earlier). The title is "A Survey of Manoeuvring Target Tracking Methods" but I can't find the link right now..
  • asked a question related to Air Traffic Control
Question
2 answers
HI, I am doing a project based in ADS-B , but now having difficuilty in finding source or generation of ADS-B packets. Can anybody have any suggestion regarding the same. Something like some software or some ADS-B data dumps which are collected by individuals or organizations.
Relevant answer
Answer
Hi Karthik, the website attached has a detailed guide on the process of decoding ADS-B packets. To generate your own packets it is simply the same process in reverse. I hope this is helpful.
  • asked a question related to Air Traffic Control
Question
10 answers
Hello everyone,
I asked a previous question as to whether dense ash aggregates (or "acc-laps") have ever been made in any wind tunnel lab thus far in their fully formed sub-spherical or ellipsoïdal shape ?
The answer has been: "not yet", even though this would allow to more closely simulate mixed phase aggregation under more realistic in situ ashcloud conditions.
I am wondering if any accretionary lapilli greater than about 10mm across or so have ever been collected immediately upon reaching the ground and studied immediately, or preserved in a cold box (to prevent them from any melting) and studied in the lab (eg. on a cryogenic SEM stage, or to measure their in situ temperature, and recover inner fluids from the intergranular space....) ?
The reason is that there is the hypothesis that they form like hailstones by riming, once they grow above a size characteristic of the drop break-up limit (5-6mm across). If this "volcanogenic hailstone" hypothesis is correct, then my expectation is that a proportion of accretionary lapilli larger than about 6mm diameter should still be frozen upon reaching the ground (especially if above-ground températures are close to 0°C; if not partial melting takes place), so that somewhat larger ones (say 10mm diameter ones) may still be frozen (despite partial melting) and still contain inner ice upon landing on the ground.
Has anyone checked for this ?
Assuming for a moment that larger sub-concentric acclaps can be sampled immediately, preserved and analysed for oxygen isotopes of any trapped ice water, then this could provide valuable data as to the temperature environments through which the acc-laps have been recycled again and again in the volcanic cloud before ultimately falling out.
Analogous oxygen isotope ratio studies  of the subconcentric layers of hailstones from severe thunderstorms have provided such information in that case.
I am looking forward to hearing back.
Best wishes and kind regards,
Gerald
Relevant answer
Answer
Hello Gerald, Ulli, Volker,
There quite a few nice examples I'm aware of where accretionary lapilli were sampled soon after fallout. One is the 2002 study by Bonadonna et al. on the 1995-1999 eruption at Montserrat (Geol. Soc. London Memoirs). Another is the 2009 eruption of Redoubt, Alaska, described by Kristi Wallace et al. in JVGR, 2013. The latter samples provided the basis of my study of 'volcanic hail' using radar observations and plume modeling with ATHAM in Nature Communications. As suggested by Gerald, these samples were indeed frozen upon landing, though that's not too surprising for an Alaskan eruption. It is clear from lab experiments that neither ice nor salt precipitates are required to grow aggregates >1cm diameter. I do not think aggregates need to undergo freezing, however, it does seem to be very common and does affect their growth rates and internal structure. 
There are also some gorgeous, layered accretionary lapilli from the 18 May 1980 eruption of Mount St. Helens, which have been archived for the past 35 years. I've recently thin-sectioned these samples and am currently working on comparing their internal structures to the eruptive stratigraphy and photographic record of the eruption dynamics. Hopefully I'll be presenting this work at the Cities on Volcanoes meeting in Chile this year. Ulli and I were talking about organizing a workshop on ash aggregation there if there's enough interest. 
All the best
Alexa
  • asked a question related to Air Traffic Control
Question
4 answers
I conduct research in air traffic control - or air traffic management.  The organizations that introduce of many new technologies and procedures (program offices) all would like the air traffic controller to see the new data that comes with these new technologies and procedures displayed on the aircraft representation.  My hypothesis so far has been that expert controllers have - through perceptual learning - managed to absorb between 7 and 10 data elements in a single fixation.  Their fixations are on average longer than what you would expect if they would read each element in a separate fixation.
The questions I have are:
  1. Is there research that supports or invalidates my hypothesis that experts - through perceptual learning - can absorb 7 to 10 data elements in a single fixation?
  2. Is there is any research available on how many data elements an expert can process in a single fixation?
  3. How long (or how many trials) will it take a novice to achieve an expert level capable of absorbing many data elements in a single fixation?
The air traffic controller's job is very dynamic and visually oriented.  To provide you some context I have attached a snapshot from a radar display used in one of our recent studies.
I am looking forward to any insights you might have - not just from the air traffic control domain, but from other domains (e.g. maritime vessel management, freight tracking, etc.) and from academia as well.
If you are interested in some of the research we do, I have a link to our publications attached.
Relevant answer
Answer
@Robert_Hutton - I am quite familiar with Klein's work on expert behavior.  The problem that we are dealing with is that our controllers are experts at what they are doing.    Controllers recognize the solution, but to be able to do so, they need to be able to perceive the situation.  At the moment we are tinkering with the basic building blocks that controllers use to build their model of that situation.  I fully agree with you that controllers are not thinking in chunks of characters, or even chunks of aircraft, but not knowing what the impact of changing the basic building blocks puts them at risk to no longer being able to use their expertise.  Compare it to changing the layout of a chessboard for chess masters or changing the content of the fields in a data block with Chinese characters.
What do we really know about experts that have looked at the display format for several decades?  How many aircraft can they track?  How much can they see in the periphery? I have worked with controllers for 20 years and I still don't have the answers, but I am trying to find if others have looked at similar issues before.
  • asked a question related to Air Traffic Control
Question
3 answers
According to the Glossary of Corpus Linguistics (Baker, Hardie and Mc. Enery 2006) there is one composed by recordings from Dallas Fort Worth, Logan International and Washington National airports. Access is paid only and available at the Linguistic Data Consortium, but since I am not really interested in the data but in the corpus structure and design I would like to know if there is another one available online or any papers about them. Thanks!
Relevant answer
Answer
Psycholinguist Rainer Dietrich of the Humboldt University (Berlin) has worked on the language of ATC. You might find references to corpora in his work.
  • asked a question related to Air Traffic Control
Question
6 answers
Hello,
I guess we have all heard about the ongoing tragic and worsening situation in Greece since 2008 for a large fraction of the population there and for refugees from Europe and elsewhere who ended up in Greece.
I am no socio-economic or political  expert but I gather that the number of people living in  precarity has soared there. I have certainly met benevolent social workers  who shared stories of despair that are hard to forget.
Greece is afflicted by a range of natural hazards and risks of disasters. It has a recurrent and documented history of such disasters.
I am wondering to what extent it is still possible for Greek scientists and/or the international community to suitably anticipate and monitor for those potential disasters and to suitably prepare for a disaster response, considering the ongoing and arguably worsening (?) situation in Greece ?
I am thinking about large forest fires (and eg. resulting biodiversity loss and atmospheric pollution), severe thunderstorms, land erosion, flash floods and mud flows on the one hand, and of tectonic earthquake and volcanic eruption hazards that may also lead to a tsunami risk in the Mediterranean on the other hand.
With the situation in Greece, aren't the vulnerabilities and the risks of impacts from such potential disasters much greater in Greece, and for some of these hazards for the European-Mediterranean regions ?
Has anyone studied how vulnerability of the Greece population to such eventualities may have increased since 2008 ?
Has anyone studied how the risks themselves for a given disaster scenario may have increased considering increased vulnerabilities and other changes in the structure of the Greece socio-politico-economic systems ?
Tectonic earthquakes from the Aegean arc submarine faults in Greece could trigger a tsunami affecting the Mediterranean region.
Can the adequate monitoring and disaster preparedness efforts still be pursued at the present time ?
And if not, what may be the wide-ranging impacts ?
The unmonitored active shallow-marine Kolumbos Bank Volcano (6km to NE of Santorini volcano) erupted explosively in 1650 AD. If it erupts again in a similar way, what may be the risk of an impact for international air traffic similar to that which related to the Eyjafjallajokull 2010 eruptions ?
What may be the tsunami risks in the Mediterranean  if the Kolumbos Bank volcano erupted explosively again ?
So to sum up, I am wondering if socio-economic-political changes in Greece since 2008 have affected vulnerability, resilience and risks for a diversity of disaster scenarios ? And also who may have studied aspects of this ?
I am also wondering to what extent scientists in Greece and elsewhere can continue to adequately monitor for, anticipate, research, sensitize for, , and generally prepare for such disasters occurring in Greece ?
And if it is the case that  the Greek scientists have difficulties continuing their work (?), to what extent the European Commission and international negociators on debt alleviation in Greece may have taken such considerations into account ?
Is this not the sort of situation making the ground much more fertile for much-enhanced impacts of geo-disasters ? Including for some that may affect much of Europe or the  Mediterranean Countries ?
Anyhow, a whole series of inter-related questions there.
I am wondering what colleagues think of all this and if some of you may have elements of answer to some of these questions ?
Many thanks in advance for any insights.
With best wishes and kindest regards,
Gerald
Relevant answer
Answer
Hello Gerard,
 In your extensive analysis you did not include the fact that the Greek population is well educated and aware of the natural dangers that hit all too common for millennia. Although the country is short of money, many research projects are funded from EE and elsewhere, so there is not a big increase of risks since 2008.  You see some of the projects mentioned above.
For example, the Greek people were well aware of tsunamis before Dec. 2004, unlike most of the rest of the world. I think Greek people are better prepared than those in Canada by comparison. In the last 10 years or so the federal funding for anything to do with the environment including research at universities in Canada has been severely CUT to avoid people get the facts on weather, natural disasters, etc. The reason is the government has been extremely pro-fossil fuel with a “forget the environment” attitude (also was the only country to officially return its signature from the Kyoto Protocol).  The result is a big problem for preparedness in a developed country and a worry for those trying to educate the public/schools, etc
  • asked a question related to Air Traffic Control
Question
3 answers
Can the presence of low-cost carriers (LCCs) increase the service quality in terms of on-time performance of all the flights landing at an airport? I recommend a very interesting paper of Branko Bubalo and Alberto Gaggero (Transport Policy, future edition) "Low-cost carrier competition and airline service quality in Europe".
Can you recommend other papers on the effect of LCCs on delays?
Relevant answer
Answer
Some suggestions:
CORREIA, T.C.V.D. ; SOARES DE MELLO, J.C.C.B. . Avaliação da eficiência das companhias aéreas brasileiras com o modelo Fuzzy-DEA. Relatórios de Pesquisa em Engenharia de Produção da UFF, v. 8, p. 5, 2008.
BARROS, T.D ; RAMOS, T.G. ; SOARES DE MELLO, J.C.C.B. . Avaliação dos atrasos em transporte aéreo com um modelo de Análise Envoltória de Dados. Relatórios de Pesquisa em Engenharia de Produção da UFF, v. 8, p. 6, 2008.
  • asked a question related to Air Traffic Control
Question
3 answers
New to learning this type of skill! Looking to select Level II base data clear air mode ONLY. Do I need to manually scan each day to find desirable times/conditions ? Or is their an option that allows you to pull out clear air mode scans from precip scans? Seems like a lot of weeding through data (which is fine) but just wanted to see if there was an easier way, or something I may be missing to do. Thanks!
Relevant answer
Answer
Something else to consider is that, if you're using precip mode as a proxy for precipitation being present in the radar scan, this isn't always perfect. Precipitation (often isolated) may still be present in clear air mode, which can affect any calculations of bird density. Likewise, radars can be in precip mode but with no precipitation around. 
  • asked a question related to Air Traffic Control
Question
10 answers
Hello,
My name is Mykolas. I live in Lithuania and currently I am studying for my pilots license and Aerospace engineering masters degree VGTU (Vilnius Gediminas Technical University).
My final paper is about an importance of English language in aviation. So I would like to ask for help:
1. Information about techniques of evaluating English knowledge (especially for evaluating professional requirements).
l
2. Any article about incidents because of miscommunication or recordings would help.
3. Expert opinion on the subject would really help.
4. Information on where I could find statistics about the traffic in airports would help.
5. Any ideas to make the subject more useful or interesting would also be very appreciated.
I will mention and give credit to anyone who will help me on my Master's dissertation.
Relevant answer
Answer
As an Air Traffic Controller, I like my instructions to be understood by the pilots. If both of us are going to follow different languages as a medium of radio telephony, then imagine the confusion! Already we are facing the problem of phonetics and different pronunciation among all the stake holders in aviation like pilots,ATCOs and ground crew.The use of non-standard procedures and phraseology can cause
misunderstanding. Incidents and accidents have occurred in which a contributing
factor has been the misunderstanding caused by the use of non-standard
phraseology.
The worst accident in aviation history i.e.,Tenerife collision between two B747s on 27/03/1977 was due to non standard R/T only. So standard and uniform R/T is a must for safe operations. Language was a part of important factor in many accidents like Milan Linate airport MD10 and a Cessna. etc
Follow the link to know about the english tests satisfying the ICAO SARPs for Language proficiency requirements.
Regarding the air traffic through out the world check ACI (www.aci.aero) or IATA (www.iata.org). They are publishing the air statistics regularly in their sites.
If you feel I may be of further helps,please inform me.
Regards and best wishes.
  • asked a question related to Air Traffic Control
Question
11 answers
Any thoughts or comments on this topic are greatly appreciated
Relevant answer
Answer
Find attached some articles I saw on the internet.
  • asked a question related to Air Traffic Control
Question
5 answers
How the the  aircraft Calculator makes correlation between the same parameters furnished by different radionav equipments to give an accurate data. I know the kalman filter is used but i want to know more and how is realized actually and nearly real time.
Relevant answer
Answer
There are several books on Kalman filtering and integrated navigation that would give you the answers, at least in part--This book by Paul Groves is the state of the art:
and the book by Britting is the classic on inertial integration:
The Kalman filter is a state observer (or Luenberger observer) or estimator that minimizes the variance of the state estimate obtained from measurements. It is able to do so in real time because it is implemented recursively--it doesn't take very much of computing or memory in each step--relative to what a batch optimization method would take for example.
Thus, the Kalman filter simply takes the various measurements in a suitable coordinate frame as output equations (e.g., y(k)=Cx(k)+D1u(k) +v) with measurement noise v, and estimates the state of the system x(k+1)=Ax(k)+B1u(k)+B2w(k) with state x and process noise w. This is usually done in the body frame of the aircraft, and then transformed suitably to LLH (latitude longitude, height), NEH (north, east, height with some local origin), or ECEF (earth centered earth fixed--usually used in GPS and satellites)  coordinates to aid the flight control and flight management systems. The state of the aircraft, or most any vehicle, is typically its 3 components each of position, velocity, attitude, and angular velocity.
The execution time for a Kalman filter on a commercial aircraft was under 5 milliseconds even in the 1990s. It assumes that the governing dynamics of the body are linear differential or difference equations, and that the measurement noise and process noise are normally distributed.
These are strong assumptions, and certainly not true for an aircraft, whose dynamics are nonlinear--as with any rigid body governed by the Euler equations. However, most aircraft operate in the regime of linear dynamics and linear aerodynamics, i.e., they mostly fly at small angles of attack in ascent or descent, and mostly straight and level. While measurement noise is normally distributed in many cases, especially when produced by circuitry (Johnson noise, shot noise and flicker), process noise is seldom well characterized, and depends upon the context, and the aspects of dynamics we choose to ignore. However, when when high sampling frequencies are available for measurements, vehicle dynamics can be approximated by simpler models to great effect.
  • asked a question related to Air Traffic Control
Question
14 answers
How can we quantify the safety of an airplane? Are there any resources to cover background / basic information to this topic?
Relevant answer
Answer
At design stages, ARP4754a and ARP4761 are referred, but purely an industry practice. The tools used are FTA or Markov Chains to derive specified hazard probability.
  • asked a question related to Air Traffic Control
Question
1 answer
I want to know if someone are studing ATM complexity using RAMS PLUS simulations to understand controllers problems, and workload. I already started this kind of study on offshore flight levels.
Relevant answer
Answer
You may want to reach out to Doug Baart and Albert Schwartz at the FAA. They use models like RAMS Plus and Agentfly all the time.